What is the units digit of (3^16)(4^13)?
Choose the correct choice:
A) 2
B) 4
C) 6
D) 7
E) 8
-&gt; The ones place of (~3)^n repeats after 4 times like 39713.   The ones place of (~4)^n repeats after 2 times like 464.   Then, 3^16=3^4*4=3^0=1.,   4^13=4^2*6+1=4^1=~4   which is (3^16)(4^13) (3^0)(~4)=(~1)(~4)=~4. Therefore, the answer is 4.
<result>B</result>
What is the units digit of (3^16)(4^13)?