HP provides a type of model name near the keyboard or screen, but this name or number is probably not sufficient to get proper support for your computer. These names or numbers often represent a series of many notebook computers that look similar, but have different options and parts.
Fundamentally, river sampling is a web-based convenience sample of opt-in participants that uses a quota sampling approach to build a study sample. The selection method is not probability based, and participants cannot be described as representing any larger defined population.
All the method are to be used for suitable type of data. Cluster sampling is one of the important methods of sampling. Sometimes, there is a very-very big and almost impossible field of study is available. Cluster sampling makes data manageable for research and further processing.