The displacement (in feet) of a particle moving in a straight line is given by s --9+16, where t is measured in seconds. (a) Find the average velocity (in ft/s) over each time Interval. (1) (4,8] P/s (1) [6,8] t/s () [8, 10] ft/s (iv) [8, 12] fus (b) Find the instantaneous velocity (in ft/s) when t8. (c) Draw the graph of s as a function of t and draw the secant lines whose slopes are the average velocities in part (a). Then select the graph of s with the tangent line whose slope is the instantaneous velocity in part (b). 10 -10 -20 0-30 10 10 -10 -15 -20 10 10 -10 15 -20 10 15 10 -10 -20 20-30 10