C. on reserves
hope this helps
Well if you mean what does the controlled part of a scientific investigation, it is the part of the investigation that will be your control or your base, untouched, original, data and such.
<span>In 1911 the Qing dynasty collapsed which brought an end more than 2000 years of imperial Chinese history. </span>
Answer:
tornadoes are formed by mixing cold and hot air together.
Explanation:
Because hot air rises, when hot air from the west, clashes with cold from the east (or visa versa) the hot air rises above the cold air and causes drag on the inside of the cold air, which makes the inside of the cold air travel at a slower rate than the outside of the cold air, which in turn makes the cold air turn in on itself.
because the cold air turns in on itself, any warmer air underneath rises above the swirl of cold air forcing it to sink to earths level. "friction" or "resistance" between the swirl of cold air and the earth's surface creates more energy that is absorbed by the cold air molecules in the swirl of air, allowing the particles to move quicker and quicker in the direction they are travelling in (a bend or circle), creating a tornado.
