Answer:
1. They should not trust this study. 2. Pseudoscience.
Explanation:
Because they drank the water and after 24 hours, they said that it was gone. Head aches go away sooner than that. Another reason is that some people could have lied about having a headache just so they could have the water or their headache could have gone away before they drank the water.
If you multiply m (the unit for wavelength) with 1s (the unit for frequency), you will get m/s, the unit for speed. Now multiply! 25 m/s is your final answer!
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