Need with this one! you don't have to give my answer, but give where i'm supposed to start. you! calculate the potential energy of a ball with a mass of 5 kg that is sitting on a roof 20 meters high. hint: use g = 10 m/s.

Asample of the male sex hormone testosterone, c19h28o2, contains 3.88×10^21 atoms of hydrogen.(a) how many atoms of carbon does it contain? (b) how many molecules of testosterone does it contain? (c) how many moles of testosterone does it contain? (d) what is the mass of this sample in grams?

An experimental procedure requires a 10 ml of acid to be dissolved

Geothermal energy for industrial use is available almost anywhere. a.true b.false