The graph on #6 describes a scatterplot. Because years of experience is the input, this makes the starting salary our output. Finding the best fitting line in a scatterplot requires the line to follow a trajectory similar to that of the points. As a result, there will be outliers. Since I don't know what "the calculator" is meant by this problem, I have used a different program. I hope it works for you. Good luck.
Answer:
For the first 30 minutes, we will have a line with a given steepness, this will represent the 30 minutes riding at a fast pace.
Then he stops for 20 minutes, we will represent this with a constant line.
Then he again moves for another 30 minutes, but with a slower pace than in the first 30 minutes, then this line will be less steep than the first line.
A sketch of this situation can be seen below.
