Suppose a data presentation is given where data values are listed in one column and the adjacent column indicates the number of times each value occurs. If this data presentation is varied by organizing the data into​ classes, the data presentation is called​ a/an . If one class in such a distribution is​ 80-89, the lower class limit is​ and the upper class limit is​ .

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?