please solve with MARKOV CHAIN

Q4 During each day, a non-negative integer number of customers arrives to a store to purchase a product. Each customer purchases a unit of the product when the product is in stock. Customers who do not find the product in stock depart without making a purchase. The store may order new units of the product at the end of the day (after that day's demand has materialized), and any such orders arrive to the store before the beginning of the next day. Each day orders are made as follows. If, at the end of the day, there are 1 or fewer units of the product in stock, then an order is placed so that there will be exactly 5 units of inventory present at the start of the next day. If there are more than 1 units of inventory present, no order is placed. The daily demands are given: X| P(x) 1 2 .2 3 .5 lw 4 .3 Please find the long run probability for all inventory levels. What is the expected number of missing demands in the long run? If we allow the backorder, do you need to update model? If your answer is yes, please show it