Ashley is selling cupcakes. it costs her $3 each week to advertise her cupcakes. it costs her $0.20 to make each cupcake, and she sells them for $1.00 each. write an equation to model the amount of profit, p, she makes from selling x cupcakes in one week. p = x − 3 p = 0.20x + 3 p = 0.8x − 3 p = 3x + 0.8

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?