7. 5 because the lowest number of pizza slices is 5. It wouldn't be 15 because there aren't 15 slices of cheese pizza.
O.K, so I'm not sure about 8. I tried to set up a timeline almost. Where I would make seven dashes to equal a week, then put the job abbreviations for the jobs underneath. I did 6 weeks and it never lined up. If you want to try that out for yourself go ahead. I'm not sure if you'll get a different outcome or not.