The graph shows the total cost of a lumber delivery based on the number of...

The graph shows a linear relationship between:

" Number of boards "

and

" Total cost "

The cost of each additional board is the rate of change, or slope, of the line.

From the graph, two labeled points are:

(0│27)

and

(10│177)

This means:

When 0 boards are ordered, the total cost is $27.

When 10 boards are ordered, the total cost is $177.

Now calculate the slope:

m=(177-27)/(10-0)

m=150/10

m=15

So each additional board costs:

$15

Therefore, the correct answer is:

▭ ( " B " )