Determination of fluid category 2. Water in fluid category 1 whose aesthetic quality is impaired owing to: 1  a change in its temperature; or. 2  the presence of substances or organisms causing a change in its taste, odour or appearance, including water in a hot water distribution system.
Credibility is defined as the quality or power of inspiring belief. Credible sources, therefore, must be reliable sources that provide information that one can believe to be true. It is important to use credible sources in an academic research paper because your audience will expect you to have backed up your assertions with credible evidence.
Credible evidence is evidence that's likely to be believed. A credible plan is one that might actually work, and a credible excuse is one your parents might actually believe. And just as credible means believable, the noun credibility means believability. (But we no longer use incredible to mean the literal opposite of credible, just as we no longer use unbelievable as the literal opposite of believable.)