Lee spends 5 hours a day working for a lawn company and 2 hours cleaning pools. he wrote this equation to represent the total number of hours he works in a day. k = 5 + 2 lee works 4 days each week. which equation would represent the total time lee works in a week? a. d = 4 + (5 · 2) b. d = 4 · (5 + 2) c. d = 4 + (5 + 2) d. d = (4 · 5) + 2

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?