The displacement (in feet) of a particle moving in a straight line is given by s = -t - 5t + 16, where t is measured in seconds. (a) Find the average velocity (in ft/s) over each time interval. (i) [4, 8] ft/s (ii) [6, 8] ft/s (iii) [8, 10] ft/s (iv) [8, 12] ft/s (b) Find the instantaneous velocity (in ft/s) when t = 8. ft/s (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 40 10 40 5 30 5 5 10 30 15 -5 5 20 10 15 -5 -10 20 10 -10 - 15 10 -15 -20 O 10 15 -20 10 15Suppose an equation of the tangent line to the curve y = f(x) at the point where a = 4 is y = 6x 2. Find the slope m of the tangent line to the graph of y = f(x) at a = 4. \"1:: Find the point of intersection of y = x) and its tangent line at a = 4. m=