Quality Bike Products (QBP) is a national distributor of bicycle products (bikes, service parts, and other accessories) for small, independent bike shops across the US.

QBP sources a specialty bike seat from a manufacturer in Germany and stocks this in its Bloomington distribution center. Weekly demand for this bike seat is normally distributed with a mean of 60 and standard deviation of 30 which is fairly steady throughout the year. The seat has a wholesale cost of $80, and the manufacturer charges $150 for shipping regardless or how many seats are ordered. The annual holding cost is $2 per seat. The seat manufacturer takes one week to supply a QBP order.

in order to minimize annual cost, how many bike seats should QPB order at a time for the Bloomington distribution center? What is the corresponding annual cost?