A) 1:4

B) 1:2

C) 4:1

D) 2:3

$\frac{\theta}{360}\times2\pi r$

$\frac{\theta}{360}\times\pi d$

equal

congruent

same

concentric

area of the half of the circle

area of the quadrant of the circle

area of three quadrant of the circle

area of the circle

Area of circle - area of sector

Area of sector - area of circle

Area of triangle - area of sector

Area of sector - area of triangle

$\frac{3}{4}\times r\times length\ of\ arc$

$\frac{1}{2}\times r\times length\ of\ arc$

$\frac{1}{4}\times r\times length\ of\ arc$

$\frac{1}{3}\times r\times length\ of\ arc$

25π - 50

25π - 100

5π - 50

5π - 100