A company sells computers; the company will order a new computer each time that a customer buys a computer. The new computer will take three days to arrive to the store (if the computer was bought in day one the new computer will be in the store at day 4). The company originally has two computers to sell. The probability that a single computer is bought by a customer in a given day is 2/3.

a) Write the Markov diagram. Define the states as the number of computers available.