Mrs. Avila is buying a wallpaper border to go on all of her kitchen walls. She wants to buy 5 extra feet of wallpaper border than she needs to be sure she has enough. She buys 55.5 feet of the border. The store owner selling the border uses the width of Mrs. Avila's kitchen to determine that the length of her kitchen must be 14.5 feet.

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?