Waterfront Fitness is planning to install 2 new indoor rowing machines (commonly referred to as "ergs"). There is robust demand for indoor rowers during the winter months, especially because the fitness club is located right next to a rowing club along the water. Their market research shows that clients who want to use these machines arrive at a rate of 7 customers per hour. If both machines are busy, Waterfront Fitness clients use other pieces of equipment, waiting for one of the ergs to become available. The erg experience is intense - the only workout on the machine is a 15-minute high-intensity interval training (HIIT) rowing segment. On average, how many Waterfront Fitness clients are using an erg at any given time? And what is the utilization of the erg machines