A local hospital wants to set up Kanban system to manage its supply of blood with the regional blood bank. The regional blood bank delivers blood to the hospital each day with a 2 order lead time (an order placed by 6 pm today will be delivered tomorrow aftermoon). Internally, the hospital purchasing group places orders for blood each day at 5 pm. Blood is measured by the pint and is shipped in containers that 7 pints. For a particular blood type, the hospital uses an average of 13 pints per day. Due to critical nature of blood shortage, the hospital wants to carry a safety stock of 3 days expected supply. How many Kanban card sets should the hospital prepare?