So, i am pretty new at a subject called "applied mathematics in economics" so take me easy : d

i have this problem:

to provide for future education costs a family considers various methods of saving. assuming that the saving lasts 10 years at an interest rate of 7,5%/year
a) calculate the value of the fund after 10 years when a single deposit of 2000£ is made annualy
b) how much should be deposited each year if the final value is 4£
c) how much should be deposited each month if the final value is 4£

the only formula i know is sn = s₀*(1+i)ⁿ but i don't think that this is applicable here?

in advance and i am really sorry if it's very easy but i just don't understand