The answer to 4 would be one because negative times negative times negative equals negative.
The answer to 5 would be 62.5. This is because 5 to the third power is 125. 125 x 4 = 500. Then 5 + 3 = 8, so you would divide 500 by 8 and get 62.5.
I hope this helped you. Comment if you have any questions. :)