Daily Demand for the Ice Creams at I-Scream Parlor Is

Daily demand for the ice creams at I-Scream parlor is normally distributed with a mean of 160 quarts and a standard deviation of 100 quarts. The owner has the ice cream supplied by a wholesaler who charges $2 per quart. The wholesaler charges a $400 delivery charge independent of order size. It takes 4 days for an order to be supplied. The opportunity cost of capital to I-Scream is estimated to be 25% per year. Assume 360 days in the year. [Show all work]
-The optimal order size of each order is:

A) 13576 quarts
B) 9600 quarts
C) 6788 quarts
D) 716 quarts
E) 506 quarts