please construct an influence diagram

Suppose that a small candy store makes Valentine's Day gift boxes that cost $13.00 and sell for $20.00. In the past, at least 50 boxes have been sold by Valentine's Day, but the actual amount is uncertain; the owner has often run short or made too many. After the holiday, any unsold boxes are discounted 50% and are eventually sold. Assume a demand of 42 and a quantity made of 53 . Construct an influence diagram for profit