A constant is something that is kept the same throughout the course of a experiment. So I would guess C) because they are not doing anything special. If it’s not C then it is A. :)
The culprit is an "arctic outbreak" that originated just above the US-Canada border, which is freezing temperatures across much of the US territory.
<h3>Arctic outbreak</h3>
"Bursts" of cold air like this are usually confined to the Arctic region thanks to a series of low-pressure systems, says the NWS. However, one of these waves advanced through Canada and "escaped" to the US.
According to experts heard by Reuters, it is a vast mass of icy air in the atmosphere, which brings with it frigid temperatures - which can be prolonged if storms form.
From this information we can conclude that according to the US Weather Service (NWS), the culprit is an "arctic outbreak" that originated just above the US-Canada border, which is freezing temperatures across much of the US territory.
Learn more about arctic in brainly.com/question/1248314
Quickly... this is a harder one, because all of possible answers are the result of interactions over a long time. However, these change the surface of the earth the fastest
1.) Volcanoes
2.) Flooding
Over a long time
1.) Through the rock cycle... earthquakes, mountain forming, etc.
2.) Melting, or forming of ice... changes sea levels
The two cateogaries of matter are intensive and extensive.
hope it helps u......
The troposphere has the highest density.