Meera works at the zoo's information desk. The total amount of time she spends giving directions is equal to 4 times the total amount of time she spends answering phone calls plus twice the amount of time she spends answering the phone and responding to emails. Which simplified expression represents the amount of time Meera spends giving directions?

Solve 3x-18=2y and 5x-6y=6 by elimination show work

Factor the polynomial, if possible. if the polynomial cannot be factored, write prime. 9n^3 + 27n^2 – 25n – 75

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?