Can I get an explanation please

An object dropped from rest from the top of a cliff falls h(t) = 4.9t2 + 50 metres in the first t seconds. a) Find the average speed during the first 3 seconds of fall. b) Find the speed of the object 3 seconds after it has been dropped. 2y For each function at the indicated x-value, find the slope of the curve; the equation of the tangent line; the equation of the normal line. y = 4x - x2, x =1 What is the rate of change of the area of a square with respect to the length of a side when the length is 5 cm? Find the value of the derivative of each of the following functions using the definition of derivative at the indicated value of a. If (x) = 5x - 9x2, a =1 5 Differentiate each of the following functions using the definition of derivative. f(x) = 19 - x 67 Sketch the graph of the derivative of the function whose graph is shown below. 7% Sketch a possible graph of f (x), given the graph of f'(x). over -7