Where's please, child? (Kids these days, no manners.)
1. The distrubtor sells cars for 12 dollars each and Eric sells the cars for 20. 20 - 12 = 8. That's 8 dollars profit per car. The flea market booth fee is 50 dollars. (What a ripoff.) So that's -50 To start off with.
D = Distrubtor cars.
S = Sales
(S - D) - 50 is the rule. (Clearication is needed, as I am can't do math so save my life.)
2. I am sorry, I can't do algebra.
3. Also algebra.
4. More algebra.