7. Falling object: An object is dropped near the surface of a planet. The time T , in seconds, it takes for the object to fall s feet is given by the formula for some constant c that depends on the...

7. Falling object: An object is dropped near the surface of a planet. The time T , in seconds, it takes for the object to fall s feet is given by the formula

for some constant c that depends on the planet.

a. On Earth the constant c is 0.25. How long does it take an object to fall 16 feet on Earth?

 b. On a certain planet an object takes 5 seconds to fall 20 feet. What is the value of the constant c for this planet?

c. If it takes 1 second for an object to fall 10 feet on a planet, how long does it take an object to fall 40 feet?