John is creating a display at the store where he works, using only canned pumpkin and canned green beans. he needs to maintain a ratio of pumpkin to green beans of 5 to 2. if he wants to use a total of 140 cans, how many cans of green beans should he use? a. 38 cans b. 40 cans c. 22 cans d. 7 cans