The answer is 2 or 0.5-because you have to multiply 3.6 to 107 then that will 385.2 and then 7.2 multiply 107 equal to 770.4.Divide all together it will give you
<span>Interest=principle x rate x time (in years)
so putting values so Interest=7500 (.042)(2) so Interest=630
7500+630=8130
Interest=500 (.071)(4)
Interest=142
500+142=64 hope it helps</span>
