Final answer:
The volume of water needed to fill an aquarium with dimensions 1.5 m in width, 4 m in length, and 3.5 m in height is 21 cubic meters or 21,000 kilograms (21 tons) of water.
Step-by-step explanation:
To find out how many cubic meters of water it will take to fill the aquarium, we can calculate the volume of the aquarium by using the formula for the volume of a rectangular prism (V = length × width × height). Given that the width is 1.5 m, the length is 4 m, and the height is 3.5 m, the volume of the aquarium would be:
V = 1.5 m × 4 m × 3.5 m = 21 m³.
Therefore, it will take 21 cubic meters of water to completely fill the aquarium. Since water has a density of 1 ton per cubic meter (1000 kg/m³), we can also calculate that the total mass of water needed to fill the aquarium would be 21,000 kg or 21 tons.