Hannah runs down the street to catch her bus. She runs for a total of 12 seconds. On the sidewalk, she runs 16 feet per second. When she crosses the street, she runs 3 feet per second. Hannah runs a total distance of 127 feet. How many seconds did Hannah spend running on the sidewalk? Enter your answer in the box.

the answer is 31.27mph

correct choice is b

step-by-step explanation:

when you calculate the average rate of change of a function, you are finding the slope of the secant line between the two points. for the function the average rate of change from point to point can be calculated as

to find the average rate of change from day 2 to day 10, note that at day 2, 8 houses were sold, so a(2,8) and at day 10, 2 houses were sold, so b(10,2). thus,

70

step-by-step explanation: