Luckily for you, question 1 and 2 are linear functions. You don’t have to do any extra calculations to find the rate of change, because it’s always consistent. Question 1 is 3, and question 2 is 5.
Question 3 involves the evaluation of a quadratic, so we have to do a little bit of math. Plug in the two endpoints of the interval into the equation to obtain their y-coordinate values; we’ll use these points to calculate the slope.