A newspaper vendor pays $12 pesos for each newspaper at the publisher and sells them for $20 pesos. If he is left with newspapers at the end of the day, he can sell them to a paper recycler for $2 pesos each. Daily demand has a normal distribution with a mean of 200 newspapers and a standard deviation of 50 newspapers. 

What is the optimal amount that the seller should buy from the publisher at the beginning of each day?