A vanilla shake machine requires a constant two minutes to make the special vanilla shake served at the Burger Shack. The machine can process one vanilla shake at a time. Requests for the special shake occur every 3 minutes, or 20 per hour on average. a. The probability that the shake machine is busy is (Enter your response rounded to two decimal places) A dollar store has eight checkout lanes. The clerks in each lane have the same abilities, whth each clerk being able to checkout a customer in 6 minutes on average. At its busiest times, customers to the dollar store arrive at the checkout counters at the rate of 30 per hour. Click the icon to view the Lq values for the quouing model. a. The average waiting time if all 8 checkout lanes are being used is minutes. (Enter your response rounded to four decimal places.) More Info