Usually to begin they use the process of relative dating,
then chemical dating. Then look at where the environment that we found the
fossil to determine if it has always been that environment. When fossil is found in marine life in a
country town suggesting that the environment was previously a marine
environment. Study the rocks that they
found the fossils to help determine a relative age. This came before that, but
after them to give us an approximate age. Then study the fossil itself to
classify it into groups to determine which branch of evolution it has come
from. Fossils can be found in rocks, bedding planes, (rock layers), trees (tree
ring dating). Mostly there are found in rocks or weathered rocks (sands, mud).
Competition among nations for control of fresh water sources is your answer I believe.
-Ama
The answer is A. because 26.25 g NaCl ( 1 mol / 59.44 g ) ( 1 mol Na / 1 mol NaCl ) ( 22.99 g / 1 mol ) = 10.15 g Na
Just look up the illness you want information about in your search engine (for example, Google, bing, or yahoo) and find a website that ends in .org, .edu, or .gov. those are the most trustworthy websites to find good information. websites that end in .com are mostly not trustworthy because anyone can have a website that ends in .com and could tell you false information. websites ending .edu are owned by colleges and have better information for you.
The seasons are caused as the earth tilted on it's axis, travels in a loop around the sun each year.Summer happens in the hemisphere tilted towards the sun, and winter happen's in the hemisphere tilted away from the sun.