Really need help practising for Exams

A factory's monthly production costs and output from a production line for circuit boards are as follows: Jan Feb Mar April May June July Aug Sept Oct Output X (units) 200 150 400 450 50 500 150 350 100 250 Costs Y (2000) 10 12 14 15 10 14 5 EX = 2,600 EY = 103 EX2 = 895,000 EY2 = 1,173 EXY = 31,350 Required: 1. Draw a scatter diagram of costs against output below. [Do not draw in your 'line of best fit'.] Instructions: 1. Use the tool provided to draw the scattergraph. 2. Once a point is plotted, click on it to see the tool options where you can amend the co- ordinates if needed. 3. To earn full credit for this graph, you must plot all required points. 2. (a) Calculate the formula of least-squares regression of costs on output. (Do not round intermediate calculations. Enter your answer in thousands. Round your answers to 2 decimal places.) Plot the regression line (calculated above) on the diagram. Instructions: Click on the line (not individual points) and a tool icon will pop up. You can use this to enter exact co-ordinates for your point as needed. (b) Explain the meaning of your regression line. (Round your variable cost answer to 1 decimal place.) 3. Estimate approximate values for the correlation coefficient, and R-squared, and explain their meanings. [Do not calculate the value of R-squared.] ezto.mheducation.com/hm.tpx 020 Cost Behaviour 4. The planned output of the factory for November is 300 circuit boards. (a) Forecast the costs for November. (Do not round intermediate calculations. Round your answer to the nearest whole number.) (b) Is the forecast reliable? O Yes O No