A variable that is changed in an investigation to see what effect it has on the dependent variable.

Measurement that is not based on any agreed standard unit (for example, hand spans, paces, cups).

Measurements based on variable quantities (for example, hand spans, paces, cups).

A study involving collection of information from primary and secondary sources.

A scientific process of answering a question, exploring an idea or solving a problem that requires activities such as planning a course of action, collecting data, interpreting data, reaching a conclusion and communicating these activities.