The grade on the west side would be the vertical rise divided by the horizontal run or 525 divided by 800' or rounded off to 66% (a steep grade as in an underground mine a grade of 25% is considered very steep for vehicles to go up or conveyors to travel). On the east side the 40% grade was obtained by dividing the 525' vertical height by the 1300' run.

Actually Welcome to the Concept of the plots and graphs.
Since, the x axis varies from -infinite to +infinite,
here, the y totally varies from -5 to +5,
hence, the option B.) is correct.
===>

First you find the zeros/x-intercepts using the factors already given in the inequality.


Therefore we make our solution using the interval notation.
$29 will be their consumer surplus.
Consumer surplus is the difference between how much a consumer is willing to pay and how much a consumer actually does pay.
$12.00 + $15.00 + $23.00 = $50.00 (How much the consumer actually pays)
$23.00 + $26.00 + $30.00 = $79.00 (How much the consumer is willing to pay)
$79.00 - $50.00 = $29.00 (Consumer surplus)