One litre of water weighs 1 kg, and one liter equals 1000 cubic cm. An aquarium is 1.9 m by 2.5 m by 0.6 m. If it is filled with water, what is the weight of the water in the tank?

First, we need to find the volume of the aquarium in cubic meters. The volume (V) of a rectangular prism (like our aquarium) can be found using the formula V = length * width * height.

So, V = 1.9 m * 2.5 m * 0.6 m = 2.85 cubic meters.

However, our conversion factors are in cubic centimeters and liters, so we need to convert our volume from cubic meters to cubic centimeters.

1 cubic meter is equal to 1,000,000 cubic centimeters, so:

V = 2.85 m^3 * 1,000,000 cm^3/m^3 = 2,850,000 cubic cm.

Now, we know that 1 liter equals 1000 cubic cm, so we convert our volume from cubic cm to liters:

V = 2,850,000 cm^3 * 1 L/1000 cm^3 = 2850 liters.

Finally, we know that 1 liter of water weighs 1 kg, so the weight of the water in the tank is:

Weight = 2850 L * 1 kg/L = 2850 kg.

So, the weight of the water in the tank is 2850 kg.