Please answer this Physics question.

5. A 92.0 kg astronaut is stranded in space and is at rest relative to his spaceship some distance away. He would like to get back to his ship, but his jetpack is malfunctioning. However, he is carrying two wrenches with masses mi = 1.5 kg and m2 = 1.8 kg. (a) He throws the first wrench (m,) with a velocity of 4.7 m/s in a direction away from the ship. What is his speed? (b) Later, he throws the second wrench (m2) in the same direction as the first wrench with a speed of 8.0 m/s. How fast is the astronaut now moving? Note: the astronaut's mass of 92.0 kg does not include the wrenches. Show all your work. U SHIP