ANSWER

Step-by-step explanation
To find the total amount of interest, we first have to find the total amount after 6 years then subtract the principal (initial amount) from it.
The total amount for monthly compounding is given by:

where
P = principal = $303
r = rate = 4.9% = 0.049
t = number of years = 6 years
Therefore, the total amount is:

Now, subtract the principal to find the interest after 6 years:

That is the interest.