How do the hydrogen-1 and hydrogen-2 isotopes differ? A. Hydrogen-2 has one neutron and hydrogen-1 has no neutrons

B. Hydrogen-2 has two protons and hydrogen-1 has one proton

C. Hydrogen-2 has one more electron than hydrogen-1

D. Hydrogen-2 has 2 neutrons and hydrogen-1 has one neutron

Okay well gravitational energy is matter forced by gravity making energy though the kinetic energy then the electric energy produces electricity from the kinetic energy and the kinetic energy gets its energy from the gravitational energy. was that the answer you wanted or something else?  

There is no reason to think the results are biased or not conducted properly but you should not assume the results are correct just because they were done in a laboratory so the answer would be c. it is likely to be reliable because the results support the conclusion presented.

Molarity is moles of solute over liters of solution. idk if that is what you are talking about, but you can convert moles of solute to grams of solute using dimensional analyzes by using molar mass found on the periodic table.