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Question 7 (5 marks) Marks The amount of fuel (in litres) consumed by a car at various speeds over a distance of 100 km is obtained. The data recorded is listed below: Speed Fuel (km/h) Consumed (L) 5 9.8 10 9.1 20 7.8 30 7.3 40 7 50 6.5 60 6.4 70 5.9 80 5.7 90 5.3 The regression output (at 10% level of significance) obtained from MS Excel is shown below: SUMMARY OUTPUT Regression Statistics Multiple 0.955455611 R Square 0.912895424 Adjusted R Square 0.902007352 Standard Error 0.458600042 Observations 10 ANOVA df MS Significance F Regression 1 17.63348802 17.63349 83.84362513 1.63209E-05 Residual Co 1.682511985 0.210314 Total 19.316 Coefficients Standard Error t Stat P-value Lower 95% Upper 95% Lower 95.0% 'pper 95.0% Intercept 9.240268456 0.27693263 33.36649 7.10459E-10 8.601660666 9.87887625 8.601660666 9.878876 Speed -0.047478428 0.00518515 -9.15662 1.63209E-05 -0.059435404 -0.03552145 -0.059435404 -0.03552 i. Write the equation of the above regression model and interpret its slope in the context of this study. [3]Question 7 (continued) Marks ii. What sample size has been used and what is the value of the correlation coefficient? [1] iii. What is the value of the coefficient of determination from the Excel output? Explain its meaning. [1]