Given,
The money deposite, P=$1500
The rate of interest is r=3%
Time, n=5 year.
a. The amount after 5 years is,
Thus the amount is $1742.75
b. Let time taken to double the money be 2.
Thus, A=2P
So,
Taking log we have,
ln2=rt
ln 2=0.03t
t=ln2/0.03=23 years
Thus the answer is 23 years.