please help with both and show all work in a cear format so that I may have a better understanding.

Use differentials and the graph of f to approximate the following. (Round your answers to two decimal places.) 4- 3- 2 (4, 2) 2 4 5 6 X (a) f(3.9) = 1.9 X (b) f(4.04) = 2.04 XThe period of a pendulum is given by the equation shown below, where _ is the length of the pendulum in feet, g is the acceleration due to gravity, and 7 is the time in seconds. T = 2T The pendulum has been subjected to an increase in temperature such that the length has increased by 1% (a) Find the approximate percent change in the period. % (b) Using the result in part (a), find the approximate error in this pendulum clock in 1 day. min