Kevin is investigating how long his phone's battery lasts (in hours) for various brightness levels (on a scale of 0-100). His data is displayed in the table and graph below. Brightness Level (x) 15 27 28 30 46 62 63 65 Hours (y) 7.5 6.1 7.1 6.3 5 5.6 4.5 4.5 10 Hours 10 20 30 40 50 70 80 90 100 11 - 1 Brightness Level a) Find the equation for the line of best fit. Keep at least 4 decimals for each parameter in the equation. b) Interpret the slope in context. O Kevin should predict an increase of 0.0519 hours per brightness level. O Kevin should predict a decrease of 0.0519 hours per brightness level. c) What does the equation predict for the number of hours the phone will last at a brightness level of 62? 71 hours d) What is the residual for the point (62,5.6)? hours