How do you explain that 21/100 is greater than 1/5?

Apyramid fits exactly inside a cube. the cube and the pyramid share the same square base, and they are both exactly the same height. the volume of the cube is 66 cubic inches. what is the volume of the pyramid? explain your answer. answer asap

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?

What is the equation of the line that passes through (3,5) and is parallel to y=2x+6