Function 1 Answer: 45
Function 1 Explanation: The rate of change (ROC) is basically the same thing as the slope of a graphed function. If you were to graph this table onto a coordinate plane, the slope of the line formed would be 45. (see Function 2 Explanation for more explanations, duh.)
Function 2 Answer: 40
Function 2 Explanation: Functions can be written in slope-intercept form, like this: y = mx + b. The m is the slope, or ROC (above), and the b is called the y-intercept, or where the line crosses the y-axis. The m in that equation is 40...
Hope that helps!! Sorry that took so long...