ASAP PLEASE

A call center receives an average of 50 calls per hour. Answering each call takes average of 5 minutes and there are 7 workers answering calls. Both call arrivals as well as service times fluctuate over time. If call arrival rate increases to 60 class per hour, how would this impact customers' average waiting time? It will increase by less than 20% It will not increase It will increase by more than 20% It will also increase by 20%