Answer: $412
Explanation:
The given principal amount P = $ 400
The rate of interest r = 4%
In decimal, the rate of interest r= 0.04
Time period t= 3 years
We know that the simple interest is given by:-

The total amount in account after 3 years = Principal+ Simple interest
⇒ The total amount in account after 3 years = $400+$12=$412