please guys help me i dont understand

Answer:
140
Step-by-step explanation:
For every 2 hours, the number goes up 140 miles.
Note: it does not ask for the MPH, it asks for Rate of Change.
Rate of Change is asking for the difference between numbers from one circumstance to the next. For example, in this question, as the table goes up 2 hours in each section, so does miles traveled. Calculate the difference in miles driven for each section to concur that the Rate of Change is 140.
Answer:
70 mph
Step-by-step explanation:
The rate of change is measured as the ratio of the difference between any 2 ordered pairs from the table
Using (4, 280 ) and (6, 420 ) , then
rate of change = [tex]\frac{420-280}{6-4}[/tex] = [tex]\frac{140}{2}[/tex] = 70 mph