Which number line shows the estimate of square root of 47 in the correct interval of integers

I=PRT
Interest=Principal times Rate times Time
Principal=amount invested in itially
Rate=rate in decimal form
time=time in years

so

given
principal=2000
rate is 3.5%=0.035
time=4yrs

so
I=(2000)(0.035)(4)
I=(8000)(0.035)
I=280

A. the interest earned was $280

B. add interest to the principal
280+2000=2280
the ballance was $280 after 4 yrs