A child in a boat throws a 4.10- package out horizontally with a speed of 10. Calculate the velocity of the boat immediately after, assuming it was...

A child in a boat throws a 4.10- package out horizontally with a speed of 10.0 . Calculate the velocity of the boat immediately after, assuming it was initially at rest. The mass of the child is 22.0 and that of the boat is 45.0 . (Take the package's direction of motion as positive.)