I believe the answer is C !
First, find moles of oxygen gas: (3.01 x10^23 molec.)/(6.02 x10^23) =0.5mol O2
Second, multiply moles by the standard molar volume of a gas at STP:(0.5mol)(22.4L) = 11.2L O2
Magnesium silicate is a compound of magnesium oxide and silicon. It is the magnesium salt of silicic acid containing an unspecified amount of water. The molecular formula can be expressed more clearly as MgSiO3.
The answer is C because you have to find acceleration.