20 Chapter 1 Introduction to Statistical Quality Control, 5th Edition by Douglas C. Montgomery. 39Copyright (c) 2005 John Wiley & Sons, Inc.Chapter 1 Introduction to Statistical Quality Control, 5th Edition by Douglas C. Montgomery. 40Copyright (c) 2005 John Wiley & Sons, Inc.
Water hardness is a measure of the dissolved mineral content of water. There are two types: the general hardness (GH) and carbonate hardness (KH). When keeping freshwater fish and plants, the GH and the KH of aquarium water should match their natural habitat.
âºâº Definition: Hectometer. A hectometre (American spelling: hectometer, abbreviation: hm) is a somewhat uncommonly used measurement of length, consisting of 100 metres or one tenth of a kilometre. âºâº Definition: Decameter. A decametre (American spelling: dekameter, symbol: dam) is a measurement of distance equal to ten metres.