Avolleyball reaches its maximum height of 13 feet, 3 seconds after its served. which of the following quadratics could model the height of the vollyball over time after it is served. select all that apply.
a: f(x)=2x^2+12x+5
b: f(x)=-2x^2+12x-5
c: f(x)=-2x^2-12x+5
d: f(x)=-2(x-3)^2+13
e: f(x)=-2(x+3)^2+13

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?