A 38 kg boy standing initially motionless on frictionless ice throws a 3.6 kg rock away from himself at a speed of 5.4 m/s. What is the boy speed after he throws the rock?

True or false graphs must include scales that increase by the same amount

See the attachment and solve question 5th

Aplayground slide is 8.80 ft long and makes an angle of 25.0° with the horizontal. a 63.0-kg child, initially at the top, slides all the way down to the bottom of the slide. (a) choosing the bottom of the slide as the reference configuration, what is the system's potential energy when the child is at the top and at the bottom of the slide? what is the change in potential energy as the child slides from the top to the bottom of the slide? (include the sign of the value in your answer.)