When you do physical exercise, the energy stored in the carbohydrate, fat, and other molecules in the cells of your body is converted to energy of motion.
a.
solar
b.
chemical
c.
heat
d.
wind

Answer is B. Chemical energy

Explanation: The chemical energy stored in the molecules in the cells of your body is converted to mechanical energy, the energy of motion, when you do physical exercise. This means that when you exercise these chemicals, carbohydrates and fats for example, are reacting and/or changing form.

Hope this helps

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.