Answer:
bcz they did not reach Europe until after the 15th century
Explanation:
A. S waves are also called secondary waves
To maintain a constant global average temperature, all of the sun's radiation that enters Earth's atmosphere must eventually be sent back to space. This is achieved through Earth's energy balance. ... ~50% of the incoming energy is absorbed by the earth's surface i.e. the land and oceans.
Explanation:
C. I believe because when you graph -4 and -2 it should make probably a straight line
Less dense then water its self