Salma is running. The number of calories she has burned varies directly with the number of minutes she has run. See the graph below. 700
500-
500
Calories
burned
00
300
100
10
30
Number of minutes
.
(a) How many minutes does Salma run per calorie burned?
minute(s)
х
5
?
(b) What is the slope of the graph?
20

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?