灰砂砖是用石灰和砂子加水加工成的，其成分为（）

A.砂子50%~60%，石灰34%~50%

B.砂子70%~78%，石灰22%~30%

C.砂子88%-90%，石灰10%~12%

D.砂子80%~86%，石灰14%~20%

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 $0.25 per box per month for record storage, what is the total amount that the company pays each month for record storage ？（）

A．$150

B．$300

C．$600

D．$1，200

E．$2,400