A certain portable monitoring device costs your clinic the equivalent of $20 per day to own and operate. You are able to rent these devices to patients for $100 per day. If the demand on a given day for these units exceeds the number you own, you must satisfy your patients' needs by obtaining the required additional units from a supplier at a cost of $150 per day (your revenue from the device, unfortunately, is still only $100 per day. You must decide how many of these units to own. your marketing department estimates that daily demand for these devices will have the following distribution