Answer:
1)"rise over run" = 1.5/18 = 3/36 = 1/12 for the 1st section to the landing
2)slope is the change in height, the vertical change, divided by the change in horizontal distance
3)2nd section has slope 1/18 and covers 9 feet. That means it rises 1/2 foot
4)slope = 1/18 = (1/2)/9
5)the door is 2 feet higher than the ground level, 1.5 + .5 = 2 feet change vertically