Answer:
A compression is a region in a longitudinal wave where the particles are closest together. ... The region where the medium is compressed is known as a compression and the region where the medium is spread out is known as a rarefaction.
Explanation:
During early civilization, the main source of fresh water was from a river. Nowadays, we have reservoirs and lakes to get fresh water. <span />
Answer:
C
Explanation:
Due to the erosion of soils, no trees to protect the ground from drying out.
<span>d. only the fittest of sperm and egg combinations will survive.
Others are external fertilization:
</span>a. all of the sperm will fertilize eggs.
b. sperm and egg will be released simultaneously.
c. the number of sperm and eggs produced will be equal.
<span>e. sperm will be protected until they can unite with the eggs.</span><span>
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