Please help me quick​

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?

If 7x=9y, y/z = 7/5 , then x/z = (a) 2/7 (b) 7/9 (c) 9/5 (d) 9/7 (e) 5/9

Fill in the blank 1. a rhombus is a rectangle a) always b) sometimes c) never 2. a square is a quadrilateral a) always b) sometimes c) never 3. a trapezoid is a kite a) always b) sometimes c) never 4. a quadrilateral is a kite a) always b) sometimes c) never 5. a square is a rhombus a) always b) sometimes c) never 6. a parallelogram is a rectangle a) always b) sometimes c) never