Answer:
Minimum height of gum = 6 foot.
Maximum height of gum = 8 foot.
Explanation:
A rider is riding a bicycle on a 6 foot wall, therefore the height of the lowest point of the rear wheel is 6 foot from the ground and highest point of the rear wheel is (6+2) foot = 8 foot ( because diameter of rear wheel =2 foot ).
If a piece of gum become stuck to the rear wheel, hence the minimum height of the gum is 6 foot from the ground and maximum height of the gum is 8 foot from the ground.