Tina had d dollars. She bought three cupcakes for her and her friends, which cost c dollars each. How much money does she have left after being so nice?

Yvaries directly as x. y =90 when x=6. find y when x=13

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?

The table shown below gives the approximate enrollment at the university of michigan every fifty years. how many more students were enrolled at the university of michigan in 1950 than in 1900?