Jimmy is on a 2.5 kg skateboard initially at rest tosses a 6 kg rock in the forward direction. If the rock has a speed of 3.1 m/s relative to the ground just after it was tossed, and Jimmy and
his skateboard move in the opposite direction at 0.7 m/s, what's Jimmy's mass? *

Water flows through a garden hose which is attached to a nozzle. the water flows through hose with a speed of 2.19 m/s and through the nozzle with a speed of 19.8 m/s. calculate the maximum height (in m) to which water could be squirted if it emerges from the nozzle and emerges with the nozzle removed.