Aron's marginal values of hamburgers and French fries, per week, are as follows: Quantity 1 Hamburgers $10 French Fries $6 23 2 8 5 3 6 4 etc. Joe's Eats charges $4 for hamburgers and $1 for fries. Jake's Eats charges $2 and $3 respectively for the same quality burgers and fries.

a. Where does Aron eat, assuming he can't buy burgers in one place and fries in the other? How many burgers and fries does he eat per week?

b. Joe's decides to institute a new pricing policy: 1 burger and I order of fries must be purchased together. How much would Aron be willing to tip the waitperson per week in order to be able to buy burgers and fries separately, if he eats at Joe's?