The time between a flash of lightning and the sound of its thunder can be used to estimate the distance from a lightning strike. the distance from the strike is the number of seconds between seeing the flash and hearing the thunder divided by 5. suppose you are 11 miles from a lightning strike. write and solve an equation to find how many seconds there would be between the flash and thunder.

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?