What are fossil fuels?why are they called so?

How do the uv rays cause damage?   what exactly causes the skin to burn;   can you be more specific about this mechanism?   3. how do photosensitive medications increase a person's sensitivity to sunlight and therefore increase their risk of getting burned?     what kind of medications can increase photo-sensitivity, can you think of some examples?

What is the code and any required modifier(s) for dipstick urinalysis, non-automated, without microscopy performed in a physician office for a medicare patient?

What are hormones? a. they are minerals needed for proper bone formation. b. they are the parts of the body targeted by endocrine glands. c. they are substances needed for muscle and nerve activity. d. they are substances released by endocrine glands.