A certain company has records stored with a record storage firm in 15-inch by 12-inch by 10-inch boxes. The boxes occupy 1.08 million cubic inches of space. If the company pays $0.5 per box per month for the record storage, what is the total amount that the company pays each month for record storage?
Choose the most appropriate option:
A) a . 150  B) b . 300  C) c . 600  D) d . 1,200  E) e . 2,400

Rationale: "volume per box : 15 x 12 x 10 = 1,800 total volume : 1 , 080,000 number of boxes : total volume / volume per box = 1 , 080,000 / 1,800 = 600 price per month : number of boxes * price per box = 600 * 0.5 = 300 answer : b"
Answer: B