Which biomolecule is the main source of energy in heterotrophic organisms?

Building glycogen from glucose molecules is an example of what

Is there any solid scientific evidence that humans have been cloned?

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?