What is the unit digit in 15^100?  Choose the correct choice from the following: A) 0 B) 1 C) 2 D) 3 E) 5
Unit digit in 15^100 = unit digit in [(15^4)^25 ]
But unit digit in 15^4=5
unit digit 15^100= 5
Answer is 5
<result>E</result>
What is the unit digit in 15^100?