b) An accountant wishes to undertake a cost analysis of electricity consumption of office heating for various maximum daily temperatures. He recorded the data over a period of 8 random days, as shown below. You may use the following Excel print-outs or summary statistics provided to answer the questions. SUMMARY OUTPUT SUMMARY STATISTICS temp Max ( C) Electricity Regression Statistics n= 8 Consumption Multiple R 0.895 X = 24 1 26 35 R Square 0.801 y = 32 2 31 20 Adjusted R Square 0.768 48.29 3 25 37 Standard Error 4.862 $3 = 101.71 4 26 24 Observations 8 SXV = -62.7143 5 14 42 6 20 41 Coefficients Standard Error t Stat P-value 7 16 40 Intercept 63.172 6.575 9.607 0.000 8 34 17 temp(C) -1.299 0.264 -4.911 0.003 i) Find the least squares regression line to predict the electricity consumption from the maximum temperature and interpret the value of the slope. ii) Predict the electricity consumption of the office when the maximum temperature is 30 C. How confident are you in this prediction