Good morning 
Answer:
6⁸
Explanation:
in this case we have at least two ways to do the calculation:
method 1:______________________
 > here we use the rule aⁿ×aⁿ = (aⁿ)²

method 2:______________________
 > here we use the rule aⁿ×aⁿ = (a×a)ⁿ

Hope this helps.
:)