Can someone please help me with the following problems on excel. Currently having trouble with all of the questions

Waiting Line Models Show all your work/calculations in a separate Excel/Word/PDF file that you will be uploading separately in the last question. Pay special attention to the Average Waiting times and Total Time Cost per hour. During the Coronavirus pandemic, Bobby's restaurant is only open for drive-through and wants to provide quick service to their customers to minimize the risk of exposure. They currently have assigned one lane to serve the drive-through crowd. Bobby recognizes that having a lengthy line is likely to deter other customers from arriving at the restaurant. Now, Bobby needs to figure out if he needs to open a second drive-through lane or not. He spends a couple of days to observe the patterns of arrival for customers and notes how long it takes for service to be provided to each customer from the time they enter the drive-through lane until they leave. He finds that the average time between the arrivals of customers is about 1 minute with a give and take of about 30 seconds (0.5 minutes). He also notices that the average service time is about 45 seconds (0.75 minutes) per customer with a give and take of about 45 seconds (0.75 minutes). He estimates the hourly cost of having a queue would be about $15 per customer lost and his cost of opening a new lane would be about $20 per hour. HINT: the give and take refers to standard deviation. Answer the questions given below in the space provided: a. What is the average number of units in the system currently? b. What would be the average time spent by each unit in queue if he opens up a second lane? minutes c. What is the difference in the total time cost per hour (TC)