Renting space at Brent's self storage costs $\$$ 10 per square feet. If Judy wants to rent a space at this storage, which has dimensions $a$ feet by $b$ feet, What will be the total cost in dollars, that she can expect to pay ?

Question

$\begin{array}{1 1} (a)\; 10(a \times b) \\ (b)\;\dfrac{a \times b}{10} \\ (c)\; 10 (\dfrac{a}{b}) \\ (d)\; \dfrac{10}{a \times b} \end{array}$