Derek and Chung work in a bakery. Lets say they have 100 hours. In one hour, Derek can produce 4 trays of cookies and 5 cakes, while Chung can produce 2 trays of cookies and 3 cakes. Which trade is possible and makes both of them better off?

a) Chung gives up 10 cakes for 16 cookies from Derek

b) Chung gives up 10 cakes for 13 cookies from Derek

c) Chung gives up 10 cakes for 7 cookies from Derek

d) Chung gives up 10 cakes for 5 cookies from Derek

e) Chung gives up 10 cakes for 4 cookies from Derek