Mel Adams has homeowners insurance that pays 90 percent of the replacement value of items damaged in a fire. He had a
fire in his kitchen, and the electric stove was damaged beyond
repair. Mel paid $350 for the stove five years ago. The cash
value of the stove before the fire was $100. A new stove with
the same features will cost $400. How much will his insurance
company pay?

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?