Answer:
Mostly correct
For Q3, you are doing great, you remembered that negative numbers can happen if the exponent is an odd number.
For Q4, I think you were confused with the fractions,
4(i)

4(ii) is also wrong but I'll let you try to fix it yourself following what I given you for 4(i). You should get 1/64
Hope this helps!
4 hours and 39 minutes before 7:53 p.m. Is 3:14 p.m.
To make a profit. The store needs to make a profit. Buy something from Walmart cheap, sell it for 60% percent more to make a 'good' profit.