A certain business produced x rakes each month from November through February and shipped x/2 rakes at the beginning of each month from March through October.The bussiness paid no storage costs for the rakes from November through February,but it paid storage costs of 0.10 dollars per rake each month from March through October for the rakes that had not been shipped.Iterms of x,what was the total storage cost,in dollars,that the business paid for the rakes for the 12 months from november through October?

A.0.40X    B.1.20x     C.1.40x  D.1.60x     E.3.20x

答案是C.

为什么呀？我就是想不通~

哪位能帮我解答一下~ 万分感谢！！！