Will give brainliiest 20 points 6th grade asap which of the sets of ordered pairs represents a function? a = {(–5, 5), (–2, 2), (2, –2), (5, –5)} b = {(4, 2), (3, –2), (9, 4), (11, –3)} (4 points) only a only b both a and b neither a nor b

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?