A local vendor at the county fair sells snow cones for $.50 each. When 250 snow cones are sold, each snow cone is estimated to have $.10 in variable costs and $.15 in fixed costs. A local school group plans on attending the fair next week and wishes to purchase 50 snowcones for $.25 each. The vendor can sell as many as 400 snowcones per day. What is the minimum price the vendor should charge for the snowcones?

a. $.75

b. $.25

c. $.10

d. $.50