Final answer:
To calculate the weight of the water in the aquarium, multiply the volume of water by the weight density of water.
Step-by-step explanation:
To calculate the weight of the water in the aquarium, we need to find the volume of water and then multiply it by the weight density of water. The volume of water can be found by multiplying the length, width, and depth of the aquarium. In this case, the volume is 4 ft * 2 ft * 4 ft = 32 cubic feet. The weight density of water is approximately 62.4 pounds per cubic foot. So, the weight of the water in the aquarium is 32 cubic feet * 62.4 pounds per cubic foot = 1996.8 pounds.