3. Marilyn hit a golf ball on the ground with her driver. Use the general function for a projectile to write a function

that shows the height in feet of her golf ball as a function

of time. The ball was hit with an initial vertical velocity of

130 feet per second.

h(t) = -16t2 + 130t

a) How long will Marilyn's ball stay in the air?

b) What was the maximum height of the ball?

Aspacecraft can attain a stable orbit 300 kilometers above earth if it reaches a velocity of 7.7 kilometers per second. the formula for a rocket's maximum velocity v in kilometers per second is vequalsminus0.0098tplusc ln upper r, where t is the firing time in seconds, c is the velocity of the exhaust in kilometers per second, and r is the ratio of the mass of the rocket filled with fuel to the mass of the rocket without fuel. find the velocity of a spacecraft whose booster rocket has a mass ratio of 20, an exhaust velocity of 2.1 km/s, and a firing time of 15 s. can the spacecraft achieve a stable orbit 300 km above earth?