WEEK 1 PART 2 Flashcards

(100 cards)

1
Q

A swimming pool can be filled by three water pipes, A, B and C. Pipe A alone can fill the pool in 12 hours. Pipe
C alone fills the pool four times as fast as pipe B alone. When all three pipes are used, the pool is filled in 3 hours.
How long would pipe B alone fill up the pool?
A. 4 hrs
C. 6 hrs
B. 5 hrs
D. 6.67 hrs

A

B. 5 hrs

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2
Q

If a card is drawn out of an ordinary deck of cards, find the probability that it is the heart?
A. 0.15
C. 0.25
B. 0.20
D. 0.30

A

C. 0.25

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2
Q

What is the area enclosed by the curve x2 + y2 − 6x − 8y + 9 = 0?
A. 16π
B. 26π
C. 36π
D. 46π

A

A. 16π

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2
Q

The area of a circle circumscribing about an equilateral triangle is 250.45 square meters. What is the area of the
triangle?
A. 93.6 m2
C. 113.6 m2
B. 103.6 m2
D. 123.6 m

A

B. 103.6 m2

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3
Q

Find the equation of a line passing through (8, -6) and perpendicular to 4x + y = 9.
A. 4x + y = 32
B. x + 4y = 32
C. 4x – y = 32
D. x – 4y = 32

A

D. x – 4y = 32

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3
Q

Water is being pumped into a conical tank at the rate of 100 𝑓𝑡3/min. The height of the tank is 20 ft and its radius
is 5 ft. How fast is the water level rising when the water height is 10 ft?
A. 15.09
B. 5.09
C. 10.09
D. 20.09

A

B. 5.09

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4
Q

A closed cylindrical tank has a capacity of 16𝜋 𝑚3. Determine the radius of the tank that requires minimum amount
of material used.
A. 1.5 m
B. 2 m
C. 0.75 m
D. 1.33 m

A

B. 2 m

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5
Q

Find the area between the curves 𝑦 = 4𝑥 − 𝑥2 and the curve y = x.
A. 9/2
C. 5/2
B. 2/9
D. 2/5

A

A. 9/2

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6
Q

Determine the volume of the solid obtained by rotating the region bounded by 𝑦 = 𝑥2 − 4𝑥 + 5, x = 1, x =4, and
the x-axis about the x-axis.
A. 47
B. 48
C. 49
D. 50

A

C. 49

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7
Q

What is the half-life of a radioactive isotope if 25% of the original mass of the isotope remains after 20 days?
A. 8 days
C. 10 days
B. 9 days
D. 12 days

A

C. 10 days

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8
Q

If P(h) pounds per square foot is the atmospheric pressure at a height h foot above sea level, then P(h) = Be−0.00003h,
where B is a constant. Given that the atmospheric pressure at sea level is 2,116 lb/ft2, find the atmospheric pressure
outside of an airplane that is 10,000 ft high?
A. 1,457.5 psf
B. 1,567.5 psf
C. 1,657.5 psf
D. 1756.5 psf

A

B. 1,567.5 psf

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9
Q

A random sample of plum tomatoes was selected from a local grocery store and their weights recorded. The mean
was 6.5 ounces with a standard deviation of 0.4 ounces. If the weights are normally distributed, what percentage
of the weights fall between 5.7 and 7.3?
A. 90.4%
B. 92.4%
C. 95.4%
D. 96.4%

A

C. 95.4%

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10
Q

In a college, a list of grades of 12 students has been declared. Their grades are given as: 85, 34, 42, 51, 84, 86, 78,
85, 87, 69, 74, 65. What is the skewness of the given data?
A. Positively skewed distribution
B. Negatively skewed distribution
C. Normal distribution
D. None of these

A

B. Negatively skewed distribution

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11
Q

. A man borrowed P5,000 from a bank and agreed to pay the loan at the end of 9 months. The bank discounted the
loan and gave him P4,000 in cash. What was the rate of discount?
A. 10%
C. 20%
B. 15%
D. 25%

A

C. 20%

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12
Q

A man invested P10,000 at an interest rate of 10% compounded annually. What will be final amount of his
investment, in terms of today’s pesos, after five years, if inflation remains the same at the rate of 8% per year?
A. Php 19,060.86
C. Php 16,096.86
B. Php 16,960.86
D. Php 10,960.86

A

D. Php 10,960.86

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13
Q

The combined mass of car and passengers travelling at 72 km/hr is 1500 kg. Find the kinetic energy of this
combined mass.
A. 300 kJ
C. 400 kJ
B. 200 kJ
D. 500 kJ

A

A. 300 kJ

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14
Q

What is the force required to accelerate amass of 30kg at a rate of 15m/s².
A. 380 N
C. 460 N
B. 450 N
D. 560 N

A

B. 450 N

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15
Q

What force is exerted by a water jet, 60 mm in diameter, if it strikes a wall at the rate of 15 m/s?
A. 636.17 N
B. 442.62 N
C. 764.23 N
D. 563.34 N

A

A. 636.17 N

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16
Q

In a bolted joint two members are connected with an axial tightening force of 2200 N. If the bolt used has metric
threads of 4 mm pitch, then torque required for achieving the tightening force is:
A. 0.7 N-m
B. 1.4 N-m
C. 1.0 N-m
D. 2.8 N-m

A

B. 1.4 N-m

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17
Q

A simply supported beam of span length 6m and 75mm diameter carries a uniformly distributed load of
1.5 kN/m. What is the maximum value of bending moment?
A. 6.75 kN-m
B. 13.5 kN-m
C. 81 kN-m
D. 125 kN-m

A

A. 6.75 kN-m

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18
Q

The length of the chest-expander spring when it is un-stretched, is 0.6 m and its stiffness is 10 N/mm. The
work done in stretching it to 1m will be:
A. 800 J
C. 3200 J
B. 1600 J
D. 6400 J

A

A. 800 J

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19
Q

Determine the atmospheric pressure at a location where barometric reading is 740 mm Hg and gravitational
acceleration is g = 9.7 m/s2. Assume the temperature of mercury to be 10°C, at which the density is 13,570 kg/m3.
A. 99.45 kPa
B. 97.41 kPa
C. 95.44 kPa
D. 98.66 kPa

A

B. 97.41 kPa

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20
Q

The barometer of a mountain hiker reads 930 mbars at the beginning of a hiking trip and 780 mbars at the end.
Neglecting the effect of altitude on local gravitational acceleration, determine the vertical distance climbed.
Assume g = 9.7 m/s2.
A. 1274.21 m
B. 1289.00 m
C. 1267.34 m
D. 1583.34 m

A

B. 1289.00 m

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21
Q

It is the circulation of water in the earth-atmosphere system.
A. Hydrology
C. Water balance
B. Hydrologic cycle
D. Water circulation

A

B. Hydrologic cycle

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22
The hydrologic process that reduces the rainfall erosivity is: A. Precipitation C. Overland flow B. Evapotranspiration D. Interception
D. Interception
23
. PAGASA raises a Yellow Rainfall Warning if the observed rainfall is: A. 7.5mm – 15mm within 1 hr B. 15mm – 30mm within 1 hr C. More than 30mm within 1hr or More than 60mm for the past 3 hrs D. None of these
A. 7.5mm – 15mm within 1 hr
24
An instrument used to measure the global radiation (the combined intensity of direct solar radiation and diffuse sky radiation). A. Pyrheliometer C. Photometer B. Pyranometer D. Pyrgeometer
B. Pyranometer
25
A stream that provides water to the water table is termed. A. Affluent C. Effluent B. Influent D. Perennial
B. Influent
26
Portion of the precipitation that makes way towards stream channels, lakes, oceans as surface or subsurface flow. A. Streamflow C. Infiltration B. Runoff D. Seepag
B. Runoff
27
Surface joining the static water levels in several wells penetrating a confined aquifer. A. Water table surface C. Capilliary fringe B. Piezometric surface D. Cone of depression
B. Piezometric surface
28
It is the flow capacity of an aquifer per unit width under unit hydraulic gradient and is equal to the product of permeability times the saturated thickness of the aquifer. A. Specific storage B. Specific retention D. Transmissibility
D. Transmissibility
29
Surveying instrument used for determining land areas in a topographic map. A. Areometer B. Erometer C. Planimeter D. Lysimeter
C. Planimeter
30
3. Which of the following indicates the principle of GPS? A. Traversing B. Trisection C. Trilateration D. Resection
C. Trilateration
31
The maximum dam height for a small water impounding project. A. 5.0 m C. 15.0 m D. 20.0 m
C. 15.0 m
32
Three tanks are installed side by side in a field to measure the ET of rice. Tank A is bottomless and is cropped, Tank B is bottomless and uncropped, Tank C has bottom and is uncropped. If the water losses after 2 rainless days are as follows: Tank A = 14mm; Tank B = 10mm; Tank C = 5mm. Determine the actual ET? A. 9.5mm/day C. 7.0mm/day B. 4.5mm/day D. 14.5mm/day
B. 4.5mm/day
33
Determine the volume of water release by lowering the piezometric surface of a confined aquifer by 5 meters over an area of A = 1km2. The aquifer is 35-meter thick and has storage coefficient of 8.3 x 10-3. A. 51000 cu.m B. 45000 cu.m C. 14000 cu.m D. 41000 cu.m
D. 41000
34
What discharge can be expected from an unconfined well 200 mm in diameter if the drawdown is 5 m in an aquifer saturated to a depth of 18 m? Assume the permeability and the radius of influence to be 20 m/day and 150 m, respectively. A. 14.3 lps B. 15.4 lps C. 13.8 lps D. 12.6 lps
B. 15.4 lps
35
. Determine the maximum total head at which a 5 hp centrifugal pump can extract water at a rate of 25 lps if pump efficiency is 65%. A. 12.48ft B. 22.48ft C. 32.48ft D. 42.48ft
C. 32.48ft
36
Given a shallow tubewell with maximum discharge of 15 lps and a total dynamic head of 7 meters. Determine the power rating of the prime mover for the pump if pump and prime mover efficiencies are 60 and 55% respectively? A. 5 hp B. 4 hp C. 6 hp D. 8 hp
B. 4 hp
37
The difference in elevation of the water surface in a pond, lake, or river from which pumped water is taken, and the water surface of the discharge canal into which the water flows from a submerged discharged pipe or the difference in elevation between the water surface in the well and the water surface of the discharged canal. A. Static head C. Drawdown B. Total dynamic head D. Net discharge head
A. Static head
38
The crop water requirement of an area grown to a certain crop refers to the amount of water used for the non consumptive demands such as land soaking and land preparation, and for the consumptive demands such as evapotranspiration requirements of the crop during its entire growth period A. Diversion Water Requirement C. Irrigation Water Requirement B. Farm Water Requirement D. Crop Water Requirement
D. Crop Water Requirement
39
2. In surface irrigation, the ratio between the gross amount of irrigation water and the net requirement of the crop is the: A. Application efficiency C. Seepage B. Deep percolation D. Runoff
A. Application efficiency
40
The maximum permissible water velocity for clay loam canal surface based on PAES 603:2016. A. 1.2 m/s B. 1 m/s C. 0.9 m/s D. 0.80 m/s
D. 0.80 m/s
41
What is the design discharge of a canal to be able to deliver a 7-day requirement of a 5-ha farm in 12 hours if the irrigation requirement is 8 mm/day? A. 65 m3/s C. 0.65 m3/s D. 0.065 m3/s
. 0.065 m3/s
42
A triangular channel with an apex angle of 75°carries a flow of 1.20 m3/sec at a depth of 0.80 m. If the bed slope is S = 0.009, find the roughness coefficient n of the channel. A. 0.00151 B. 0.0151 C. 0.151 D. None of these
B. 0.0151
43
What is the base of the most efficient trapezoidal concrete open channel if discharge is 100 m3/s and velocity is 2 m/s? A. 6.14 m C. 7.21 m D. 14.6 m
A. 6.14 m
44
What design depth of open channel would you recommend to carry 100 cumecs or cubic meters/sec with a velocity of 5 mps? Use the most efficient of all trapezoidal cross-sections. A. 1.4 m C. 3.4 m B. 2.4 m D. 1.3 m
C. 3.4 m
45
The soil has a field capacity and permanent wilting point of 27% and 13%, respectively. What is the readily available moisture in cm of water per cm of soil if the bulk density is 1.25 g/cc? A. 10.25 cm/m B. 17.5 cm/m C. 13.12 cm/m D. 14.0 cm/m
C. 13.12 cm/m
46
By float method, the surface water velocity of a stream was 0.5 meter per sec. The estimated cross-sectional area of the stream was 4.86 m2. What is the average discharge of the stream? A. 1.494 m3/s B. 1944 lps C. 7 m3/min D. 0.90 lpm\
B. 1944 lps
47
Compute the unidirectional flow in two parallel drains 600 m apart if the soil hydraulic conductivity is 12 m/day and the water level at the drains are 7.5 and 10.2 meters. A. 0.01 m/day B. 0.02 m/day C. 0.03 m/day D. 0.04 m/day
B. 0.02 m/day
48
Used if the entire area is to be drained and is usually more economic. Laterals enter the submain from one side only to minimize the double drainage that occurs near the submain. A. Border-strip flooding B. Ordinary flooding C. Herringbone Pattern D. Gridiron Layout
D. Gridiron Layout
49
This is used if the main source of excess water is drainage from hill lands. The drains are placed along the toe of the slope to protect the bottom land A. Intercepting Drain B. Ordinary flooding C. Herringbone Pattern D. Gridiron Layout
A. Intercepting Drain
50
For a 9m x 9m sprinkler spacing, what is the design sprinkler throw for a 40% overlap? A. 3.3m C. 5.3m B. 4.3m D. 6.3m
. 6.3m
51
Sugarcane is to be irrigated using sprinkler irrigation. The sprinkler spacing is 12.2 m while the lateral spacing is 18.3 m. The soil water holding capacity is 120 mm/m, crop rooting depth is 1.0 m and management allowable deficit is 45%. If the irrigation period is 12 hrs and the application efficiency is 70%, the required sprinkler discharge is: A. 0.2 lps C. 0.4 lps B. 0.3 lps D. 0.5 lps
C. 0.4 lps
52
A banana plantation is to be irrigated by sprinklers with a nozzle discharge of 0.5 lps. The sprinkler spacing is 40ft and the lateral spacing is 60ft. The soil water holding capacity is 120mm/m, crop rooting depth is 1.0m and management allowable deficit is 60%. If the application efficiency is to be 75%, the irrigation period should be: A. 12 hrs B. 13 hrs C. 14 hrs D. 15 hrs
A. 12 hrs
52
In a drip system, the allowable pressure variation in a lateral with minimum and average head of 1.51 and 1.38 m respectively is: A. 0.185 psi B. 0.462 psi C. 0.370 psi D. 0.130 psi
B. 0.462 psi
53
The soil has a field capacity and permanent wilting point of 27% and 13%, respectively. What is the readily available moisture in cm of water per cm of soil if the bulk density is 1.25 g/cc? A. 10.25 cm/m C. 13.12 cm/m D. 14.0 cm/m
C. 13.12 cm/m
54
The soil has a field capacity of 22% and a permanent wilting point of 12 %, both on a dry mass basis. The apparent specific gravity is 1.4. If the rootzone depth is 1.0 m and the management allowable deficit is 50%, the net application depth is: A. 50 mm C. 70 mm D. 80 mm
C. 70 mm
55
An 8 mm rainfall was measured by a USWB standard raingauge, 8 inches in diameter. Determines the depth in the inner cylinder whose area is 1/10 of the catch area: A. 0.8 cm C. 80 mm B. 259 mm
C. 80 mm
56
The maximum dam height for a small farm reservoir? A. 3.0 m B. 4.0 m C. 5.0 m D. 6.0 m
c. 5.0 m
57
What is the potential SFR capacity if the surface area is 25 m x 30 m and the depth is 1.5 m? A. 1125 m3 C. 375 m3 B. 750 m3 D. None of these
C. 375 m3
58
In selecting the optimum capacity of the reservoir of a SWIM Project for irrigation purposes, the reliability of the reservoir should be above. A. 80-85% B. 30-40% C. 50-60% D. 60-70%
A. 80-85%
59
Small water impounding management SWIM Project, in general, are those small-scale water impounding dams which have structural heights of not more than. A. 45 m B. 50 m C. 30 m D. 100 m
C. 30 m
60
A trapezoidal concrete gravity dam has inclined upstream wall. Resisting moment relative to the dam toe is 263,953.2 tonne-meters while overturning moment is 96,233.3 tonne-meters per meter of dam width at deepest section. What is the safety factor against overturning? Is it safe? A. 0.36, unsafe B. 2.74, safe C. 3. 96, safe D. 5.48, excessively safe
B. 2.74, safe
61
A 3-m wide and 13.4-m high spillway with a short approach channel was designed for a maximum discharge of 6.0 m3/s. Assuming a head loss down the spillway of 0.25 m, the initial depth d1 prior to the hydraulic jump is: A. 0.10 m C. 0.15 m B. 0.12 m D. 0.20 m
B. 0.12 m
61
Determine the crest length of a structure for a chute spillway for a design flow of 1.4 cms and a maximum water level at the inlet is 0.5 m, the coefficient of discharge is 1.66: A. 0.54 m C. 4.38 m B. 2.38 m D. 3.28 m
B. 2.38 m
61
A dam spillway is to be designed to have a service life of 50 years. If the acceptable risk for structural failure due to excessive flood discharge is 10%, the spillway should be designed for a return period of: A. 175 years C. 375 years B. 275 years D. 475 years
D. 475 years
62
A method of erosion control accomplished by constructing broad channels or benches across the slope is: A. Contouring B. Terracing D. Grassed waterway
B. Terracing
63
An imaginary line of constant elevation on the surface of the ground. A. Horizontal interval B. Vertical Interval C. Contour map D. Contour line
D. Contour line
64
A type of terrace usually used for 9-24% slope characterized by breaking the slope at certain intervals by a ridge and a flat portion to trap runoff. A. Bench terrace B. Zingg terrace C. Broad-based terrace D. Manning’s terrace
B. Zingg terrace
65
On a 20% hill slope, it is proposed to construct bench terraces with 1.1 batter slope, if the vertical interval is 2 m, what is the width of the terrace? A. 10 m C. 8 m D. 16 m
A. 10 m
66
An unlined trapezoidal irrigation canal is to carry a maximum discharge of 2,800lps. The side slope is to be set at 1:1. The head loss over a 1km distance is 1m. The Manning’s roughness coefficient is 0.025. If the maximum permissible velocity is 0.92m/s, the design depth should be: A. 10.95m C. 2.95m B. 0.95m D. 5.95m
B. 0.95m
67
A concrete-lined trapezoidal canal is to carry a maximum discharge of 2.0 m3/s. The required head loss over a horizontal distance of 1 km is 2.0 m. The side slope is to be set at 1:1 and the permissible b/d ratio is 3. If the Manning’s roughness coefficient is 0.015, the design depth required is: A. 0.42 m C. 0.64 m B. 0.56 m D. 0.78 m
B. 0.56 m
68
An outlet for a reservoir embankment is to be designed for a critical demand flow of 5.0 m3/s and a critical head of 8.0 m. Assuming a total head loss of 1.5 m, a recommendable RCP diameter is: A. 25 in C. 30 in B. 28 in D. 32 in
C. 30 in
69
Breeding and growout production of commercially important marine species are grown in zonified marine cages which the Bureau of Fisheries and Aquatic Resources refers to as: A. Industrial cage parks C. Seawater cage farms B. Ocean cage parks D. Mariculture parks
D. Mariculture parks
70
Area with more species of corals, fish, and pharmaceutical marine products than any other marine environment on Earth: A. Biome B. Ocean C. Coral Triangle D. Freshwater
C. Coral Triangle
71
Occurs when excessive nutrients (e.g. NPK fertilizers in agricultural fields) are accumulated in different bodies of water that leads to algal blooms and fish kills. A. Nitrification B. Eutrophication C. Desertification D. Water degradation
B. Eutrophication
72
Without additional aeration, a continuous supply of 70 gpm of oxygenated, good quality flow-through water can support approximately. A. 265 kg fish B. 300 kg fish C. 365 kg fish D. 400 kg fish
A. 265 kg fish
73
The process of converting water and carbon dioxide into sugar using chlorophyll and light energy accompanied by the production of oxygen by green plants. A. Respiration C. Transpiration B. Oxidation D. Photosynthesis
D. Photosynthesis
74
Plants living more than one year but, in some cases, producing seed in the first year and every season thereafter. A. Annual C. Biennial B. Quarter-annual D. Perennial
D. Perennial
75
Plants that grow in dry situation and regularly endures and survive drought is called. A. Xarophytes C. Bryophytes B. Hydrophytes D. Spermatophyte
A. Xarophytes
76
Refers to the beneficial species of insects which feed or attack other insects. A. Natural enemies B. Pest C. Pathogen D. Prey
A. Natural enemies
76
Control of disease through crop rotation falls under what method of plant disease control. A. Biological method B. Cultural method D. Chemical method
B. Cultural methoD
76
Rocks that were formed from the partial melting of existing rocks due heat, pressure chemical action. A. Metamorphic rocks B. Sedimentary rocks C. Igneous rocks D. Volcanic rocks
A. Metamorphic rocks
76
Which of the following soil microorganism is the most numerous in soils?? A. Bacteria C. Virus D. Actinomycetes
A. Bacteria
77
It is a process of destroying most disease-producing microorganisms and limiting fermentation in milk subjected to heating for a definite time at a definite temperature and thereafter cooling it immediately. A. Evaporation C. Pasteurization D. Homogenization
C. Pasteurization
78
The scientific name for Oriental Cattle. A. Bos taurus B. Bos indicus C. Bubalus bubalis D. Sus scrofa
B. Bos indicus
79
The period from conception to birth of the young. A. Mastication B. Lactation C. Fecundation D. Gestation
D. Gestation
80
The scientific name of bighead carp is: A. Kappaphycus B. Aristichthys nobilis C. Chanos chanos D. Oreochromis niloticus
B. Aristichthys nobilis
81
Perna viridis is the scientific name of: A. Slipper cupped oyster B. Green mussel C. Giant clam D. Mud crab
B. Green mussel
82
1. Eye ablation is a way of inducing females to spawn in: A. Milkfish B. Oysters C. Mussels D. Shrimp
D. Shrimp
83
Water like in estuarine areas with intermediate salinity due to the mixing of fresh and sea water is referred to as: A. Freshwater C. Seawater B. Brackishwater D. Marine water
B. Brackishwater
84
pecies that are capable of causing extinctions of native plants and animals, reducing biodiversity, competing with native organisms for limited resources, and altering habitats: A. Exotic species C. Invasive species B. Native species D. Endemic species
C. Invasive species
85
It is also called geosphere and it consists of the solid Earth that includes the continental and ocean. as well as various layers of Earth’s interior: A. Hydrosphere C. Biosphere B. Atmosphere D. Lithosphere
D. Lithosphere
86
The boundary between troposphere and stratosphere is known as: A. Tropopause C. Stratopause B. Thermopause D. Mesopause
A. Tropopause
86
At what time where the sun is farthest distance from the earth: A. The permeability is high C. Perihelion B. Aphelion D. None of these
B. Aphelion
87
. A surveyor has taken the measurements shown in the figure below. Find the distance across the lake. A. 975.8 ft B. 978.5 ft C. 978 ft D. 979 ft
B. 978.5 ft
88
By rational method, determine the design peak runoff for a 50-year return period. The watershed consists of 50-ha, one third in rotation meadow and the remainder on row crops on the contour. The hydrologic soil group is B and the time of concentration is 30 min. The rainfall intensity for the 50-year return period is 25 mm/hr. The runoff coefficient, C, for soil group B, is 0.29 for meadow and 0.63 for row crop. A. 0.87 m3/s C. 1.82 m3/s D. None of these
C. 1.82 m3/s
89
The agrometeorological station uses electronic rain gage. The rainfall depths were recorded on June 1, 2022 as follows: 2 mm from 6:00 to 8:00 A.M., 7 mm from 8:00 to 10:00 A.M., 9 mm rom 12:00 noon to 2:00 P.M. and zero rainfall for all other times of the day and the previous day. What is the rainfall intensity recorded on June 1, 2022? A. 0.75 mm/hr B. 2 mm/hr C. 4 mm/hr D. 3 mm/hr
C. 4 mm/hr
90
A farmer asked you, an engineer, “What is the erosion rate in my 10-hectare farm with an average slope of 3%?” The following were determined during you visit: slope-length factor is 1.0; soil type is loam with a factor 0.25; cropping management factor of 0.6 for overgrazed; conservation practice is conventional with factor 1.0; and from your assessment the rainfall factor is 178. What will you answer the farmer? A. 16.7mm/yr B. 26.7mm/yr C. 36.7mm/yr D. 46.7mm/yr
B. 26.7mm/yr