please help me with this solution and please show some work

Q8.)

8. The efficiency of electric bikes depends on the speed they are used as indicated in the following table and dot plot. We also have the output from the spreadsheet function "linest' applied to this data with speed as the independent variable and efficiency as the dependent variable. speed mph 7 11 12 13 15 16 20 21 23 24 20 efficiency m/wH 54.2 41.3 51.0 43.8 46.2 29.8 26.5 25.4 29.5 16.9 19.4 linest: -1.95 68.23 0.27 B8 V 0.85 5.22 51.97 9100 1416.11 245.22 60.0 40.0 20.0 0.0 10 15 20 25 a. What is the equation of the best fit regression line? b. What is the efficiency estimate for a speed of 25 mph? c. What is the correlation coefficient? d. Is this a good fit