¿por qué tantos trabajadores migrantes fueron a california en la década de 1930?

Marine exptoration of oil uses seismic waves to locate oil in the seabed. what is a negative impact from seismic waves on the aquatic ecosystem of the ocean? a.seismic waves kill microoganisms b.seismic waves disrupts the sand and causes seafloor erosion c.seismic waves have virtually no adverse affects on marine life d.seismic waves damage the sonar that dolphins and whales use to orient themselves underwater

How were castas paintings used to stabilize a society?

How does the balance of trade look different in the us today vs hot it looked in the 70's