In a Fourth-Grade Classroom, a Teacher Rewards His Students for Keeping

question 129

True/False

In a fourth-grade classroom, a teacher rewards his students for keeping their desks clean by awarding them stars for every day they do this. At the end of the school year, the stars can be redeemed for prizes such as colouring books or pencil sets. This teacher is using what is called a token economy.

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Definitions:

QRS Segment

Part of an electrocardiogram (ECG) representing the depolarization of the heart's ventricles, which precedes the contraction of the ventricles.

ECG

An electrocardiogram, a test that measures the electrical activity of the heart to detect heart abnormalities.

Ventricule

A term often misspelled or used interchangeably with ventricle, which typically refers to one of the two lower chambers of the heart or a cavity in the brain that contains cerebrospinal fluid.

PR Interval

A measurement on an ECG that represents the time between the start of the atrial depolarization (P wave) and the start of the QRS complex, indicative of atrioventricular conduction.