What is the unit digit in (4137)^754?  Choose the correct option
A) 1
B) 3
C) 7
D) 5
E) 9
Unit digit in (4137)^754 = Unit digit in {[(4137)^4]^188 x (4137)^2}   Unit digit of 7^4 is 1 and of 4137^2 is 9.   so the required unit digit = 1 x 9 = 9.   Answer 9) 9.
<result>E</result>
What is the unit digit in (4137)^754?