ABC Analysis: A classification of items in an inventory according to importance defined in terms of criteria such as sales volume and purchase volume. ABC Classification: Classification of a group of items in decreasing order of annual dollar volume or other criteria. This array is then split into three classes called A, B, and C. The A group represents 10 to 20% by number of items, and 50 to 70% by projected dollar volume. The next grouping, B, represents about 20% of the items and 20% of the dollare volume.
Fuel cells (batteries) provide another use option, just as they were utilized by NASA. Fuel cells basically reverse electrolysisâhydrogen and oxygen are combined to produce electricity. Hydrogen fuel cells are very efficient and produce only water as a by-product, but they are expensive to build. With technological advances, small fuel cells could someday power electric vehicles and larger fuel cells could provide electricity in remote areas. Because of the cost, hydrogen will not produce electricity on a
A single hydrogen fuel cell delivers a low voltage, so manufacturers stack fuel cells together in a series, as in a dry-cell battery. The more layers, the higher the voltage. Electrical current, meanwhile, has to do with surface area. The greater the surface area of the electrodes, the greater the current.