Key terms & definitions

A number or operation that acts on another quantity; in this topic, a fraction or percentage acts by multiplication.

A symbol or keyword that performs an operation on one or more values.

The rules determining which operations are evaluated first in an expression.

A person whose interpretations and views influence other members of a particular group.

A rear chamber or porch of a Greek temple. In the Parthenon, the western chamber was used to store public funds.

A Roman law restricting women’s possession of gold, multi-coloured clothing and carriage travel, with a religious-festival exception to the travel restriction.

A fortified settlement in Iron Age Europe; the plural is oppida. Such settlements could be important centres of local power.

An infection that takes advantage of a weakened immune system and would normally be controlled more effectively.

A sample consisting of people who are available and willing to participate at the time of the research; also called an opportunity sample.

Selecting observations or participants because they are conveniently or safely available.

A person's access to chances to develop and succeed, such as education, employment and participation in society.

The benefit of the next-best alternative given up when money or other resources are committed to a particular choice.

The next best alternative given up when a choice is made.

Selecting readily available members of the population who meet the study criteria; also called convenience sampling.

A technique in which a researcher selects people who are available and willing to participate at the time.

Selecting participants who are available when and where the researcher recruits them.

The number with the same magnitude but the opposite sign; for example, the opposite of $-4$ is $4$.

The angle directly across the triangle from a particular side; side $a$ is opposite angle $A$.

The side across from the acute angle being considered in a right-angled triangle.

Disagreement with a government or its policies, which may be expressed privately or publicly.

An audience interpretation that recognises but rejects a product’s intended meaning.

The prolonged, unjust treatment or control of people by those with power.

The unjust use of power to control, harm or deny rights to other people.

The point at the centre of a thin lens through which a ray is represented as continuing undeviated.

A storage medium read using a laser, such as a CD, DVD or Blu-ray disc.

A thin strand of glass or plastic that guides light, including infrared signals, along its length.

A thin, transparent fibre along which light signals travel to carry information.

Storage that uses a laser to read patterns on the surface of a disc.

The pattern of light reaching the eyes from the environment, containing information about objects and surfaces.

The nerve that carries electrical impulses from the eye to the brain.