***Be careful while writing the units in your exam. I have written answers in m/km as well as in m/m***
The correct answers are:
(2)
(or 0.03 m/m)
(3)
(and NO! The car will not make it because gradient of the hill is greater than the maximum gradient the car can climb) (or 0.960 m/m)
(4)
(and YES! The car WILL make it because gradient of the hill is less than the maximum gradient the car can climb) (or 0.053 m/m)
(5) Road-A's gradient:
, and Road-B's gradient:
(Road-B will be easier to ride up). (Road-A 0.1 m/m; Road-B 0.010 m/m)
(7)
(and YES! Johnny's tricycle WILL fall apart)
(8)
(or 2.27272 m/m)
(9)
(or 0.7535 m/m)— If the sign is important then it should be
as the plane is descending (slope is negative).
(10)
(or 0.5435 m/m) — If the sign is important then it should be
as the plane is descending (slope is negative).
Explanations:
Important notes:
- Please see the picture attached with the answer for (few) question.
- I shall use meter per kilometer (or feet/miles) unit for gradient for all the questions in explanation, as many parts in the question-sheet deal with this unit for gradient.
For all these questions, remember the following formula:

(2) As you can see in the picture attached, the horizontal distance is 100km, and the vertical distance is 3000 m. Therefore, the gradient will be:

(3) As you can see in the picture attached, the horizontal distance is 0.5km, and the vertical distance is 500-20=480m. Therefore, the gradient will be:

As 960 > 500, the car will not make it.
(4) As you can see in the picture attached, the horizontal distance is 1.5km, and the vertical distance is 100-20=80m. Therefore, the gradient will be:

As 53.33 < 500, the car WILL make it.
(5) The elevation is 500 m.
For Road-A (which is 5 km long):

For Road-B (which is 50 km long):

Since 10 < 100, therefore, we can say that Road-B will be easier to ride up.
(7) As you can see in the picture attached, the horizontal distance is 0.2mi, and the vertical distance is 300-35=265ft. Therefore, the gradient will be:

As 1325 > 100, Johnny's tricycle WILL fall apart.
(8) As you can see in the picture attached, the horizontal distance is 22km, and the vertical distance is 50000 m. Therefore, the gradient will be:

(9) As you can see in the picture attached, the horizontal distance is 4.3km, and the vertical distance is 3560-320=3240m. Therefore, the gradient will be:

(10) As you can see in the picture attached, the horizontal distance is 7.2km, and the vertical distance is 4567-654=3913m. Therefore, the gradient will be:

NOTE FOR QUESTIONS 9 and 10: One thing to note here is that, as the plane is descending, the gradient should be negative (as the path has a negative slope).