1. The problem statement, all variables and given/known data In this problem you will do numerical computer calculations. A skydiver of mass 75.0 kg jumps out of a plane at an altitude of 30.0 km above the surface of the Earth. His parachute fails to open. Assume there is no horizontal motion and the initial velocity is zero. We ultimately will want to do a calculation that includes variation in the drag force due to variation in atmospheric density as well as the variation of the gravitational force with altitude. But we will start simple a) Calculate the time to fall to the ground with no air resistance and no variation in g. Compare your result to the analytical result and refine the computer code to achieve no worse than 0.1% accuracy by adjusting the time step. b) Now include a retarding force of F(v) = c*v2, where c=0.500 kg/m and is constant. You should be able to compare your result to an analytic result from problem 3. 2. Relevant equations 3. The attempt at a solution this is my program import numpy as np # numerical calculation for falling body with constant #gravitational force only # # gravitational acceleration in m/s^2 g = 9.81 # mass in kg m = 75. #drag coeffcient in kg/m c = 0.5 # initial position (measuring down to be positive) in m y = 0. # initial velocity in m/s y1 = 0. # time interval in seconds dt = 0.01 a =  # acceleration array v =  # velocity array p =  # position array i = 0 while y<30000.: i = i + 1 y2 = g - (c*y1**2.)/m # this the differential equation that describes the motion (y2 = a ) y = y + y1 * dt y1 = y1 + y2 * dt p.append(y) v.append(y1) a.append(y2) print(i*dt) in the end i get t = 784.78 s for the total time but how can i be sure about this number?