Schools A and B are competing in an academic contest. At the beginning of the final round, School A has 174 points and School B has 102 points. In the final round, correct answers earn 10 points and incorrect answers lose 6 points. School A gives the same number of correct and incorrect answers during the final round. School B gives no incorrect answers and the same number of correct answers as School A. The contest ends with a tie. How many correct answers does each school give during the final round?

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?