A small construction company borrowed $500000 to purchase some machinery. Some of the money was borrowed at 9% interest, some at 10% interest, and the remainder at 12% interest. The annual interest was $52000. the amount borrowed at 10% was 2.5 times the amount borrowed at 9%. How much was borrowed at each amount?​

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?