20 Points--Algebra 1

Answer:
y = 400(1.01)^t
Step-by-step explanation:
Firstly find the rate
(Take any balance for two years, e. g 400 and 404,412.12 and 416.24,etc to get simple interest)
408.04-404= 4.04
I=(P*R*T)/100
From which R=(100*I)/PT
R= 100*4.04/404*1
R=1%
Using compound interest formula
A =P(1+r/100)^n
where n is time
substituting each value
y = 400(1+1/100)^t
y= 400(1.01)^t