Help on this question please

First choice: 2

Explanation:

There are 2 phosphorous (P) in the substance.

Ignore the strontium (Sr3) part because you are looking to isolate the P from (PO4)2.

Break the chemical equation apart to get 1 Phosphorous atom, and 4 Oxygen atoms.

Now, multiple 1 by 2 because that are 2 phosphate to get 2 phosphorous atoms.

whats the meaning of /

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.