# Momentum Question Help

Alright, so im working on my physics homework right now and theres two problems that I have no idea what I need to do. Im not even sure what formulas i need to start with or anything. i was hoping someone on here might be able to help me out with these two questions.

Question #1

"An astronaut is working around the Internation Space Station (ISS) attached by a tether cord. The snap on the tether fails and he finds himself adrift, but stationary relative to the ISS. This astronaut was a former physics student and knows that if he can throw some objects away from himself in the right direction, he can properl himself back to the station. His tool kit has a 1.20 kg torque wrench, a .70 kg nut driver, and a .35kg bolt. The astronaut, his suit, an all of his gear have an initial mass of 105.00 kg. if he throws away each of the items in his tool kit at 3.0m/s, one at a time, what will be his final speed relative to the ISS?"

Question #2

"Two identical air track gliders of mass .125kg approach each other at equal speeds of .500 m/s. Assume that the two gliders are a system. Since the center of mass of a system of objects is the point at which all of the mass can be assumed to be concentrated, choose a convenient coordinate system and determine the location of the center of mass for the following times :
a) .5 seconds before the collision
b) collision
c) .5seconds after the collision.

Question #3 (goes with question #2)

Now, determine the speed of the center of mass of a system of the two gliders if glider 1 is stationary and glider 2 approaches glider 1 at .500 m/s to the right. what is the momentum of the system in this case?"