The area of the circle with radius r is
A = πr²
The rate of change of area with respect to time is

The rate of change of the radius is given as

Therefore

When r = 10 ft, obtain

Answer: - 40π ft²/s (or - 127.5 ft²/s)
Answer:
E=0
Explanation:
The electric field at the centre of the shell is zero because total enclosed charge in the nucleus is zero
Answer:
older plates that are subducting almost perpendicularly, and when the location is far away from the edge of other tectonic plates, are the most likely areas for copper deposits to form
Explanation:
32 degrees Fahrenheit
And
0 degrees Celsius
Answer:

Explanation:
m = Masa del coche
g = Aceleración debida a la gravedad = 
h = Altura = 
v = Velocidad del automóvil en la parte inferior de la pista
Aquí asumimos que el automóvil desciende verticalmente. La energía potencial del automóvil se completará convertida en energía cinética en la parte inferior de la pista ya que no hay pérdida de energía.

La velocidad máxima que puede alcanzar el coche es
.