A tile factory earns money by charging a flat fee for delivery and a sales price of $0.25 per tile. One customer paid a
total of $3,000 for 10,000 tiles. The equation y-3.000 = 0.25(x - 10,000) models the revenue of the tile factory,
where x is the number of tiles and y is the total cost to the customer
Which function describes the revenue of the tile factory in terms of tiles sold?
What is the flat fee for delivery?

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?