A boy who is 1.5 meters tall is standing 15 meters away from a 6.5 meter wall. He throws a ball at a 45 degree angle. gravity is 10m/s2 with no air resistance. Find the minimum velocity needed in order for the ball to reach the wall. I dont know what formulas to use since im not given the time

What is the rate of change in a objects position?

The star betelgeuse is about 600 light-years away. if it explodes tonight, a. we'll know because debris from the explosion will rain down on us from space.b. we'll know it immediately because it will be brighter than the full moon in the sky.c. we won't know about it until 600 years from now.d. none of the above.

In a hydrogen molecule there are a total of four charges, 2 protons in the two nuclei, and 2 electrons. how many unique charge-pairs are there (without double counting)?