Answer: Negative integer is used to indicate the new water level i.e. 2 feet below the dock.
Step-by-step explanation:
Since we have given that
The water level is 3 feet below your dock.
It means the level of water = -3 feet
The tide goes out, and the water level lowers 1 foot
The level of water = -1 feet
A storm surge comes in, and the water level rises 2 feet.
The level of water = +2 feet
According to question, it becomes

Hence, Negative integer is used to indicate the new water level i.e. 2 feet below the dock.