because they like it
Fish tanks are measured primarily by their capacity. In the U.S. they use gallons as the main unit. A fish tank can be anywhere from 1 gallon in capacity to 200+ gallons.
Volume can be measured in liters or cubic meters, and all of their derivatives.
Volume can be measured in liters or cubic meters, and all of their derivatives.
The capacity of a bathtub could be appropriately measured in liters.
Capacity can be measured using both the metric system and customary units. In the metric system, capacity is typically measured in liters or milliliters, while in the customary system, it is measured in ounces, cups, pints, quarts, and gallons.
Capacity isn't a unit at all. It's a characteristic, or a property of an item, which can be measured in whatever suitable unit. Capacity of batteries is measured in amp hours. Capacity of a gas tank can come in either liters or gallons.
A pitcher's capacity is typically measured in liters or gallons, depending on the region. In the USA, pitchers are commonly sized in quarts, while in other countries, they may be measured in liters.
Engine capacity is measured in cubic inches, cubic centimeters or liters; a common Ford V8 (eight cylinder) engine is a 302. Three hundred cubic inches or 5 liters. Capacity is measured by the amount (volume) of air in the cylinder it displaces. Here is the link, http://en.wikipedia.org/wiki/Engine_displacement
Your question is too vague, the capacity of what? Capacity of containers can be measured with volume, and units would be liters, quarts, or gallons. Capacity of computer systems is often measured in bytes, with units like megabytes or gigabytes. And capacity of some things like trucks and ships is often measured by weight, so the units would be kilograms, pounds, or tons.
you can mesure a drink, or a regular shallow pool
Fridges are measured in liters because it is a more accurate way to indicate their storage capacity compared to using cubic feet. Liters are used as a standard unit of volume in many countries, making it easier for consumers to understand the internal space available for storing items in a fridge.
Backpacks are measured in liters because it provides a standardized way to indicate the volume or capacity of the backpack. This measurement helps consumers understand how much gear or items the backpack can hold, making it easier to choose the right size for their needs.