国外购买药品英文翻译

Dear Mr./Ms.
Please answer my questions as the following:
(亲爱的先生/女士，请回答我下列问题)

(请问这3种的浓度都是10mg吗??)All the three kind of drugs has the same density as 10mg?

(5和20Ampules/Phials这表示什么,是表示5瓶和20瓶的意思吗?
)5 Ampules/Phials and 20 Ampules/Phials mean what? They mean: 5 bottles and 20 bottles?

(第一个和第二个产品是一摸一样的,为什么价格相差这么多?)Why the first and the second look almost the same, but why the big price gap in between?

(我想购买的是10mg/20ml这种规格的该买哪种?)If I want to buy 10mg/20ml specification, which one you suggest for me?

Thanks!
XXX
(谢谢！)
(人面爱桃花)