The volunteers placed a race marker in the ground every five thousand yards. Every eight thousand yards, the volunteers set up a refreshment station. There are 1,760 yards in one mile. About how many miles will a participant have to travel before seeing both a refreshment station and race marker at the same location? Calculate the answer to the nearest tenth of a mile. Fill in the blank. miles

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?