Can someone please help with this?!

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?

You work in a hospital that has 9 floors. you need to see 3 patients on each floor. how many patients do you need to see in all?

In 2000 there were 100 rabbits in central park the population increased by 16% each year ? write a function to illustrate the situation. how many rabbits were in central park in 2005 . predict how many rabbits there will be at the end of this year we are in 2018?