HELP PLEASE!!!!

Question

The question is: Carmella works 37.5 h per week for Century Home selling electronics equipment. She earns a base salary of $12/h and receives a commission of 5 cents for every dollar of sales she make.
Her chart goes like:
WSales($):Commission($): TotalSalary($)
0 0 -blank-
1000 50 -blank-
2000 -blank- -blank-
3000 -blank- -blank-
4000 -blank- -blank-
5000 -blank- -blank-
6000 -blank- -blank-

Then:Carmella's friends Maria and Sam work for two other electronics companies. The also work 37.5 h per week. Maria earns $8/h with a 10% commission and Sam earns $18/h with no commission.
a) One week, Carmella and Sam earned the same total salary. Determine each person's total sales and salary.
HOW DO I ANSWER THIS?! I TRIED TO DO THE ABOVE CHART FOR ALL THREE FRIENDS TO GET THE INFO TO GRAPH BUT THERE IS NO WEEKLY SALES I SEE WHEN SAM AND CARMELLA HAVE THE SAME TOTAL SALARY.
WHAT AM I DOING WRONG?!
I FILLED OUT THE CHARTS LIKE BUT FOR TOTAL SALARY, AM I SUPPOSED TO ADD THE PREVIOUS TOTAL SALARY TO THE NEXT ONE OR WHAT? PLEASE HELP ME WITH THIS QUESTION, PLEASE!

Answer 1

on x sales,

c = 12*37.5 + .05x
m = 8*37.5 + .10x
s = 18*37.5

during the week, sam made 675.00
so, we need
12*37.5 + .05x = 675.00
x = 4500
c = 450(salary) + 225(commission) = 675

Answer 2

:"%^^"&"^"*%*%*$*$*$$&$&$*:&"*:*85464

Answer 3

The table shows the shipping-fee options for two online marketplaces. If you sell a model train car for $135, which is the lesser fee?