A taxi company charges a $2.00 base fare plus an additional fare based on a per-mile rate and a per-
minute rate. Ryan's first taxi ride was 3.0 miles, took
7 minutes, and cost $8.50. His second taxi ride was
7.0 miles, took 14 minutes, and cost $16.00. If his
third taxi ride took 10 minutes and cost $13.50,
approximately how many miles was the third taxi
ride?

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?