If rupee one produces rupees nine over a period of 42 years, find the rate of simple interest?	Choose the correct choice from the following options:
A) 22 1/7 %  B) 22 3/2 %  C) 21 3/7 %  D) 22 1/2 %  E) 22 1/2 %
9 = (1*42*R)/100   R = 21 3/7 %   Answer:21 3/7 %
<result>C</result>
If rupee one produces rupees nine over a period of 42 years, find the rate of simple interest?