Answer:r=16 ft , d =32 ft (a)
Step-by-step explanation:
c=2 pi r
32pi= 2 x pi x r
r=32 pi/2pi
r= 16
diameter = radius x 2
d= 16 x 2
d = 32
the difference from 40000 to the future value in 2020, namely 5 years later is simply the yield or interest amount.