金融计算题，简答类的。求详细过程

easy corporate finance questions.you need to draw a time line which indicates 30 payments of deposits and 35 withdraws.the point ** the total withdraw in time zero should equal to the 30 total deposits in time zero.you need to concern that not all the withdraws are the same.and you cannot use single one formular.on her 65th birthday,there will be a one off withdraw.
p.s.watch out the withdrawing happens after the last deposit.th** ** really important.and the last withdraw ** at the end of 95th year.
a)first asume each deposit ** a amount.asume today ** year 0
by the end of year 30 fv(30)=(a/r)*((1+r^30)-1=a*((1.08^30)-1)/0.08
by the end of year 65 pv(65)=35000*(1-(1.08^-35))/0.08
plus the one off payment at the end of year 35 pv(35)=250000/(1.08^5)
fv(30)=pv(35)+pv(65)=578055.6868[here i d**count all the amount to year 30 not year 0,you can do year 0 one,or year 65 one.the results should be the same.the point ** to draw a time line,it ** very helpful]
a=$5102.75
b)all right let assume each deposti ** b amount.
future value of the 30 deposit at the end of year 30 fv(30)=b*((1.08^30)-1)/0.08
plus the deposit at year 0.fv(30')=50000*1.08^31=[be carefore,there are 31 years between the end of year 30 and the begining of year 0].
fromquestion a)we already know that the amount she need at the end of year 30 to meet the next 35 withdraws.which ** 578055.6868=fv(30)+fv(30')
b=$306.07
c)lets assume each deposit ** c amount.
fv(30)=c*((1.08^25)-1)/0.08
fromquestion a we got the total amount she will use after retirement at year 30 ** 578055.6868=fv(30)
c=$7907.10
d)do thequestion again but th** time use interest 5%
ps.calculate again using casio fx82.im not using casio,just the calculator installed in the computer.maybe there are some calsulatino m**takes.be carefore