不懂如何張這句中文轉成英文

Could you calculate for me how many boxes I can ship for $12?
I send about 40 to 50 boxes per month. Could I get a discounted price?
Or, what is the minimum that I need to send to get a discounted rate?
Do you provide Fedex service?

此外，問題中的「張」字是白字，該寫為「將」。

Please calculate the number of boxes that can be delivered for $12.
Is there any discount if I need to deliver about 40-50 boxes every month?
If not, how can I get a lower price for the delivery?
Would Fedex Express provide services for your side/ country?

Freight charges $12 can transport how many boxes does it have at most, please help me to calculate that I want about 40-50 boxes every month, where do you have fedex express delivery will just have more favourable prices or how much is wanted Could you tell me whether there are more favourable prices