请教金融数学问题.明天就要交了,各位好心人求解答...

请教金融数学问题.明天就要交了,各位好心人求解答...
In the context that,
(a)Suppose that you deposit $10000 at the end of each year for 5 years. The bank offers you 5% annual interest rate and compounded yearly. Find the future value at the end of 5th year, assuming that no withdrawals are made during the 5-year period.
In (a), if you deposit the same amount of money at the beginning of each year, what is the future value at the end of 5th year? Assume that all other conditions are same.
What is the difference between when you deposit money at the end of each year and when you deposit money at the beginning of each year? I have calculated the first sub problem and I am about to show you my answer for that matter.
According to the compound interest formula A=P(1+r%/n)^nt,
A = 10000(1+(5%/1))^(1*5)
A=10000*(1.05^5)
A=10000*1.27628156
A=12762.8156
And I have also plugged in the data in one compound interest calculation website and the answer is the same as I have got in here, which is A=12762.8156.
Here comes to what I want to ask. What is the second sub problem all about? How is it different from the first one as it just says that you deposit money at the beginning of each year rather than at the end of each year? Please help me with this financial mathematical question, thank you!

这不是很简单的技术经济学问题么?
就是年初和年末投资有什么不同,一万块钱,投5年,年利息5%,按年计息,复利计算,第5年末一次性付清
这就是基本的现金流量图计算
再问： 我就是想问年初和年末有什麽不同啊。。。第一题我算出来了，第二题是年初请问怎麼算。。
再答： 年末就相当于年初往后推一年啊。就是总数差了一年的利息，年初投资是年末投资的1.05倍