Mg3(PO4)2 - the molar mass would be 262g/mol, which is 100%
Atomic mass of Mg is 24, since we have 3Mg we multiply by 3 and get a mass of 72
262 : 100% = 72 : x%
x = 72*100 / 262
x = 27.5%
And do that for every element — get the molar mass of P and multiply by 2, use a ratio, and get the molar mass of O and multiply by 8 and use ratios :)
The answer is Vestigal. It is a type of anatomical structure that no longer serves any function. Over time they are no longer needed in the body. Apart from the wisdom tooth, another example would be the tail bone which has no use for humans.
Kinetic energy on mass. gravity, and speed
I think that the answer is a size and speed