In a certain city, 80 percent of the households have cable television, and 60 percent of the households have videocassette recorders. if there are 150,000 households in the city, then the number of households that have both cable television and videocassette recorders could be any number from: a. 30,000 to 90,000 inclusiveb. 30,000 to 120,000 inclusivec. 60,000 to 90,000 inclusived. 60,000 to 120,000 inclusivee. 90,000 to 120,000 inclusive

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?