Why is it logical to assume that they hydrogen ion concentration in an aqueous solution of a strong monoproctic acid equals the molarity of the acid?

It is logical to assume that they hydrogen ion concentration in an aqueous solution of a strong monoproctic acid equals the molarity of the acid because ions which are charged,for example ammonium ion (NH4+), which can be derived by the addition of a proton to a molecular base.

Most likely a is the answer - because  you generate   38 atp's but also consume an atp.   each atp gives approx. less than 4 kcal so probably a is the closest answer.

The answer is 323 g.