sara says, If you subtract 11 from my number and multiply the difference by - 2, the result is - 30. what is saras number?

How do i make someone brainliest? (if you answer me, i might be able to make you brainliest! )

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?

Georgia needs to buy flea treatment for her dog. pet store 1 is offering the flea treatment for 40 percent off plus an additional 25 percent off their regular price of $33. pet store 2 is offering the same flea treatment for 55 percent off plus an additional 5 percent off their regular price of $34. which location is offering the better price and how much cheaper is it? the flea treatment is $0.31 cheaper at pet store 2. the flea treatment is $1.05 cheaper at pet store 2. the flea treatment is $2.05 cheaper at pet store 1. the flea treatment is $2.36 cheaper at pet store 1.