Assume that all grade-point averages are to be standardized on a scale between 0 and 5. ·How many grade-point averages must be obtained so that the sample mean is within 0.012 of the population mean? Assume that a 98% confidence level is desired. If using the range rule of thumb, σ can be estimated as range 4= 5−0 4=1.25.
·Does the sample size seem practical?

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?