Approximately 3.25 x 10 cubic yards of material were used to
build boulder dam on the arizona-nevada border. the new
comelia tailings dam in arizona used 2.74 x10 cubic yards of
material
how many more cubic yards of material were used to build the
cornelia tailings dam than boulder dam?

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?