$500 will become $1000 in 7 years find the rate of interest?  Choose the correct choice from the following options
A) A)10%
B) B)20%
C) C)14.29%
D) D)30%
E) E)50%
SI = simple interest = A-P = 1000-500= 
<gadget id="calculator">1000-500</gadget>
<output>500</output>
$500   R= 100SI/PT = 100*500/500*7 =14.29%   Answer is 14.29%
<result>C</result>
$500 will become $1000 in 7 years find the rate of interest?