An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does havedevices to measure distance and time accurately. she lmows her own mass is 7& 4 kg, but she is unsure of the mass of alarge gas canister in the airless rocket, when this canister is approaching her at 3.50 m/s, she pushes against it, whichslows it down to 1.20 m/s (but does not reverse it) and gives her a speed of 240 m/s. (a) what is the mass of this canister? (b) how much kinetic energy is "lost" in this collision, and what happens to that energy?