Kristen Ashford purchased the subscribers list for Wind Surfing magazine. She plans to survey a sample of the subscribers before using the list in her mail order business. She chooses the first 100 of the 5,000 names. Her sample is a .
a) simple random sample
b) stratified sample
c) systematic sample
d) convenience sample
e) cluster sample

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?