Answer:
 2/π ≈ 0.637 m/s
Step-by-step explanation:
The rate of change of area with respect to time is ...
 A = πr²
 dA/dt = 2πr·dr/dt
Filling in given values in the above equations, we can find r and dr/dt.
 25π = πr²  ⇒  r = 5
 20 = 2π·5·dr/dt
 dr/dt = 20/(10π) = 2/π . . . . meters per second
The radius is increasing at the rate of 2/π ≈ 0.637 meters per second.
Answer:
C if your doing prep
Step-by-step explanation:
math
