Twenty-seven ordinary piecewise function images are related to practical problems, and each image corresponds to a situation. The increase and decrease speed of the first function is the overall water inflow and drainage speed.

The second question of 28 questions lacks obvious thinking process guidance, so it is not easy for candidates to think of cutting and spelling graphics to find the area, and they need to use the second conclusion given, so that they cannot complete the following solution.

It is difficult for students with weak thinking ability to get high marks.