arcs and sectors

Question 1

area of a sector:

Answer 1

angle / 360 x π x radius ^2

Question 2

arc length of a sector:

Answer 2

angle / 360 x 2 x π x radius

Question 3

perimeter of a sector:

Answer 3

arc length + 2 x radius

Question 4

area of a circle:

Answer 4

π x r ^2

Question 5

circumference of a circle:

Answer 5

2 x π x radius