Question 973893
2 raised to a power goes 2,4,8,6
to the 9th power 512, then 1024, then 2048, 4096.
Divide the exponent by 4 and see what is left over
2^31 is 2^28 (which ends in 6).  The next three end in 2,4,and 8.  The remainder will be 8.

2^69 will have 17 repeats of the pattern and will end in 2 for 2^69.  The remainder will be 2, when divided by 5.