<span>Which of the following are indicators of a chemical change? Select all that apply.
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These are the answers:
<span>color change
temperature change
precipitate formation
gas formation
Hope this helps.
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The wavelength is the distance between one crest/trough to another crest/trough. On the image, it's basically the length between each peak of the wave. You can see that the distance between peaks in wave A are much shorter than the distance between the peaks in wave B.
Thus, wave B has the longer wavelength.