(a) Using the data below for variables X (output) and Y (total cost), calculate an equation to determine the expected level of costs, for any given volume of output, using the least squares method. Time period 1 Output ('000 units) 20 Total cost (5000) 2 16 82 3 4 24 22 70 90 5 18 85 73 (b) Prepare a budget for total costs if output is 22,000 units. (c) Confirm that the degree of correlation between output and costs is high by calculating the correlation coefficient.