Which of the following relationships represents a function?
A.
x -6 5 -2 -2
y 8 6 8 7

B.
x -6 5 -6 7
y 8 8 14 7

C.
x -6 5 -3 10
y 8 6 14 8

D.
x -6 5 -2 5
y 8 6 8 7

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?