which of the following options is the correct value of r, given the equation 6^r +1^(-r) = 217?  Choose the correct choice from the following choices:
A) 5
B) 7
C) 3
D) 2
E) 0
Plugging in the various option into the equation to find out which is correct:   6^r +1^(-r) = 217   6^3 +1^(-3) = 217 Ans. 3
<result>C</result>
which of the following options is the correct value of r, given the equation 6^r +1^(-r) = 217?