Question

click on the number that shows a compression.
compression (longitudinal) wave
direction of travel
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Explanation:

In a longitudinal wave, compression is the region where the medium particles are tightly packed together. The circled number points to the tightly coiled (compressed) section of the spring, while 3 points to the rarefaction (spread-out particles) and 2 points to a full wavelength.

Answer:

The number that shows a compression is the circled number (the one pointing to the tightly packed coils on the left).