Question: On a boat in a lake, there is a rope ladder. The rope ladder is 5 inches off the water. Then one day the lake waters rise 5 inches. How high off the water is the ladder now?
Answer: 5 inches. The boat rises with the water, so the height of the ladder doesn't change.
Question: A semi truck weighing exactly 10,000 pounds gets onto a bridge that is 100 miles long. The bridge's weight limit is exactly 10,000 pounds, any more will break the bridge. After going about 80 miles down the bridge a small bird lands on the truck.
Answer: Nothing, after traveling 80 miles the truck will have surely burnt enough fuel to allow the bird to land on the truck without breaking the bridge.