You need to work about 12.5 hours because from your gas station job, since you work 30 hours every week, times that by 8.75$ which equals 262.5$ at the end of the week, so subtract 262.5 from 400 which is 137.5, then you need to dived that by 11 since its $ per hour, after doing that you get 12.5 hours, so you would have to work 12.5 hours at your landscaper job
Question 3 is D and question 4 is c for what I tell of the pictire
Not sure about the summer part, but the answer should be 1 / 6. Maybe your question is wrong.
For calculating the mean, you want to add up all of the numbers then divide by how many numbers there are. So you'd do:
5+10+12+4+6+11+13+5 then divide that by 8
The answer to your question is: 8.25