State two condition necessary for a solid to float in a liquid

it's density must be less than water

law of floatation

wt of the immerged body = wt of the water displaced by it

X-rays have so much energy they can go right through your muscles and fat.

Explanation:

There are actually more ways to fill in those two blanks... Different parts of the body absorb x-rays in varying degrees, but soft tissues (like skin, muscles, fat, and organs) allow most of the X-rays to pass through.