4000 ml to kl plis help mee

Ahot-air balloon is 11.0 m above the ground and rising at a speed of 7.00 m/s. a ball is thrown horizontally from the balloon basket at a speed of 9.00 m/s. ignore friction and air resistance and find the speed of the ball when it strikes the ground.

Why should the wavelength scale of spectroscope be calibrated

In a star, nuclear fusion occurs in the a. photosphere. b. corona. c. radiative zone. d. core.