The sales data for July and August of a frozen yogurt shop are approximately normal. The mean daily sales for July were $$270,$ with a standard deviation of $$30.$ On the $15$th of July, the shop sold $$315$ of yogurt. The mean daily sales for August were $$250,$ with a standard deviation of $$25.$ On the $15$th of August, the shop sold $$300$ of yogurt. Which month had a higher z$-$score for sales on the $15$th$,$ and what is the value of that z$-$score? A$.)$ August, with a z$-$score of $1\mathrm{.}67$ B$.)$ July, with a z$-$score of $1\mathrm{.}8$ C$.)$ August, with a z$-$score of $2$ D$.)$ July, with a z$-$score of $1\mathrm{.}5$