Given: Years: 1, 2, 3, 4, 5, 6, 7, 8 Sales (in $100,000): 6.1, 6.4, 8.3, 8.8, 5.1, 9.2, 7.3, 12.5 US births (in millions): 2.9, 3.4, 3.5, 3.1, 3.8, 2.8, 4.2, 3.7 To do: a. Determine a regression equation for predicting sales based on births using years 2 through 8 as the baseline. We know: The regression equation can be represented as: To calculate 'a' and 'b,' we can use the least-squares method. The formula for 'b' (slope) is: The formula for 'a' (intercept) is: Explanation: n is the number of data points. x is the independent variable (births). y is the dependent variable (sales). denotes summation (sum of all values). The residents of Lee city deposit their refuse on the curbside, at the start of each working day. The amount of refuse placed at curbside at the start of each day is an uncertain quantity whose probability distribution is given below Refuse(in tons ) 15 20 25 30 35 40 45 50 55 60 probability 0.025 0.075 0.15 0.2 0.175 0.15 0.1 0.075 0.025 0.025 The quantities of refuse produced on different days are all independent of one another. Refuse is collected by crews. Each crew can collect 5 tons of refuse per eight-hour working day. Each crew consists of two members, and each member receives $20/ hour($160/day). Whatever refuse remains at the end of the work day must be collected that evening by a special crew, who picks up the surplus at a price of $175/ton. Determine the number of regular crews that minimizes the expected cost of garbage collection and the associated expected cost of garbage collection