How Many One-To-One Correspondences Are There Between the Sets $\{ x , y , z , u , v \}$

question 79

Multiple Choice

How many one-to-one correspondences are there between the sets $\{ x , y , z , u , v \}$ and $\{ 2,4,6,7,9 \}$ if in each correspondence $x$ must correspond to 7 and $z$ to 6 ?

• A) 120
• B) 16
• C) 21
• D) 6

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Definitions:

Endogenous Substance

A compound or chemical that is produced within an organism or a biological system rather than being introduced from the environment.

Gastric Acid

The hydrochloric acid secreted by the stomach lining, essential for the digestive process.

Neurotransmitter

Chemical substances that transmit signals across a synapse from one neuron to another.

Serotonin

A neurotransmitter that affects mood, appetite, sleep, and other cognitive and physiological processes.