In what type of soil would you recommend locating a drinking water well? Options:
Sand
Gravel
Soil
Clay

Explain why.

Sand

Explanation:

A well should be placed so that contamination from any source moves away from the well and not toward it.

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.