On average, the market price of roses on Valentine's Day is $10 per rose. Interestingly, when rose-recipients are asked how much they would be willing to pay for roses themselves, they value them less than the Valentine's Day market price. The graph below shows (i) solid blue columns representing the prices a rose-recipient would willing to pay for each additional rose if they were purchasing roses for themselves, and (ii) the solid red columns representing the marginal benefit of the 'warm fuzzy feeling' the rose-recipient gets from being given a rose by their beloved. What is the socially optimal number of roses that should be purchased, and why