In the figure below,S is the center of the circle.Suppose that JK=7,LM=7,NS=6,and PS=4x-6.Find the following.

Future value annuity is calculated using the formula:
FV=P[((1+r/100n)^nt-1)/r]
where:
P=principle
r=rate
t=time
n=number of terms:
Thus:
A monthly deposit of $300, at the rate of 5% in (65-25)=40 years will give us:
FV=300[((1+5/1200)^480-1)/(5/1200)]
FV=$457, 806.05

b] A monthly deposit of $400, at the rate of 5% in 40 years will give us:
FV=400[((1+5/1200)^480-1)/(5/1200)]
FV=$610,408.06