An enumeration district is a geographic area determined for purposes of taking the census. In one city there may be many enumeration districts, so once you enter a city, county, or state, you can narrow your results by entering street level information, or investigate enumeration district maps, or descriptions.
P wave. 1. a longitudinal earthquake wave that travels through the interior of the earth and is usually the first conspicuous wave to be recorded by a seismograph. Also called primary wave. Compare L wave, S wave. The P wave is admitted to be the wave of auricular contraction. p wave.
Best Answer: P waves travel through both solids and liquids but slow down in the liquid layers of the Earth. S waves travel through solids but are absorbed by the liquid layers of the Earth. S waves travel slower than P waves and are transverse (P Waves are compressional). These factors could be why P waves don't have the energy to pass through liquids. Also, this is why there is a large S wave shadow zone.