Can you help me?

A passenger on a commercial airliner wants to estimate the takeoff speed of the airplane. They decide to perform an experiment using a house key, a piece of string, and some stiff cardboard. The passenger ties one end of the string to the key and attaches the other end of the string to the cardboard, as shown in the figure below. Prior to takeoff, when the plane is stationary, the passenger marks the position of the keyhole on the cardboard to provide a vertical reference line. During takeoff, the passenger recorded the position of the keyhole at 5-s intervals until the plane started to lift off the ground. The results are shown in the table below. A. Draw a graph that shows the acceleration of the plane as a function of time. (Hint: What simplifying assumption can you make about how the acceleration of the key compares to the acceleration of the plane?) B. Using the passenger's data, estimate the takeoff speed of the plane. t (s) e (o) O O 5 6.2 10 11.0 15 15.7 O 20 21.8 25 26.1