Please write formula out and show excel steps thank you kindly

Problem 3 (from Case 9.3 of the textbook] 50 points total Nolan Banks is an auditor for the Public Service Commission for the state of Georgia. The Public Service Commission is a government agency responsible for ensuring that utility companies throughout the state manage their operations efficiently so that they can provide quality services to the public at fair prices. Georgia is the largest state cast of the Mississippi River, and various communities and regions throughout the state have different companies that provide water, power, and phone service. These companies have a monopoly in the areas they serve and therefore, could take unfair advantage of the public. One of Nolan's jobs is to visit the companies and audit their financial records to detect whether or not any abuse is occurring. A major problem Nolan faces in his job is determining whether the expenses reported by the utility companies are reasonable. For example, when he reviews a financial report for a local phone company, he might see cable line maintenance costs of $1,345,948, and he needs to determine if this amount is reasonable. This determination is complicated by the fact that the companies differ in sizeso he cannot compare the costs of one company directly to another. Similarly, he cannot come up with a simple ratio to determine costs (such as 2% for the ratio of line maintenance costs to total revenue) because a single ratio might not be appropriate for companies of different sizes. To help solve this problem, Nolan wants you to build a regression model to estimate what level of line maintenance expense would be expected for companies of different sizes. One measure of size for a phone company is the number of customers it has. Nolan collected the data shown below representing the number of customers and line maintenance expenses of 12 companies he audited in the past year and determined were being run in a reasonably efficient manner. Customers (in 1000s) 25.3 36.4 37.9 45.9 53.4 66.8 78.4 82.6 93.8 97.5 105.7 124.3 Line Maint. Expense (in $1000s) 484.6 6723 839.4 694.9 836.4 681.9 1.087.0 1,095.6 1,563.1 1,377.9 1,711.7 2.138.6