From my previous answer:
i = √-1
i2 = -1
i3 = -i
i4 = 1
i5 = i ...... and so on. The cycle repeats.
These questions are easier than they look. You need to find out the remainder of the exponent after dividing by 4. That will tell you where in the cycle you are. Give it a go!
By the way, did you know that to find out the remainder when dividing by 4 you only need to check the last 4 digits? Why do you think that is? (Your teacher is trying to be funny with those giant exponents - math humor ☝¬‿¬☝)