Question

A fighter plane travelling horizontally at 1.0x10^2m/s drops a rocket from a height of -1.00x10^3m.

Answer 1

The vertical component of rocket's velocity as it reaches the ground (assuming it does not have an engine) is

$$v_y=\sqrt{2gh}=\sqrt{2·9.8·1000}=140\text{ m/s}.$$