Melvin plays tennis and swims for a total of 110 minutes every day. he plays tennis for 40 minutes longer than he swims.

part a: write a pair of linear equations to show the relationship between the number of minutes melvin plays tennis (x) and the number of minutes he swims (y) every day. (5 points)

part b: how much time does melvin spend swimming every day? show your work. (3 points)

part c: is it possible for melvin to have spent 70 minutes playing tennis if he plays and swims for a total of exactly 110 minutes and plays tennis for 40 minutes longer than he swims? explain your reasoning. (2 points)

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?