First we'll find the Interest no. 1, which is simple interest, assuming the time 1 year:
S.I= PRT/100
S.I= 780*5.2*1/100
S.I=$40.56
Now we'll find interest no.2, which is compound interest, time is 6 years, Principal amount (780) will remain the same as well as the rate thus (putting in the formula of compound interest- annual- ):