$600 will become $720 in 4 years find the rate of interest?  Choices:	A) 10%	B) 15%	C) 5%	D) 7%	E) 20%
SI = simple interest = A-P = 720-600= 
<gadget id="calculator">720-600</gadget>
<output>120</output>
$120   R= 100SI/PT = 100*120/600*4 =5%   Answer is 5%
<result>C</result>
$600 will become $720 in 4 years find the rate of interest?