what is the units digit of the expression 17^7-2?
Select:  A) 1  B) 2  C) 3  D) 7  E) 9
7^1=7   7^2=49   7^3=343   7^4=1(last digit)   7^5=7(last digit) and the cycle repeats after every 4 powers   Therefore, last digit of 17^7=3   3-2= 
<gadget id="calculator">3-2</gadget>
<output>1</output>
1   1nswer 1
<result>A</result>
what is the units digit of the expression 17^7-2?