Mike walked 450 m west. he then turned and walked 150 m to the east in 300 seconds. what is his velocity?

What is binding energy and separation energy

Imagine you are standing in the antarctic during the southern hemisphere summer. the sky is clear and blue. there are no clouds in the sky. your shadow is cast on the icy ground. what is the color of the shadow?

Hydrogen and helium are both members of?