It is important to have a control group in an experimental investigation because if the experiment did not have the control group the data collected would not be accurate. For example if you're testing water turning into ice but you use a different freezer or ice tray for each experiment then there are some elements that would make your data inaccurate.
This co -relates to continent drift theory.
This theory states that the outer rigid layer of the earth or the lithosphere is divided into a couple of dozen "plates" that move around across he earth's surface relative to each other. That is why Alfred Wegener noticed that Africa and South America seem to fit together.
Though Wegener's hypothesis lacked a geological mechanism to explain how the continents could drift across the earth's surface as he proposed.
It is the Wrangell-St.Elias in Alaska.
It is 8,323,148 acres
It was established in December of 1980
Answer:
Your answer is in the pic
Answer:
Explanation:
m = Mass of each the cars = 
= Initial velocity of first car = 3.46 m/s
= Initial velocity of the other two cars = 1.4 m/s
v = Velocity of combined mass
As the momentum is conserved in the system we have
Speed of the three coupled cars after the collision is .
As energy in the system is conserved we have
The kinetic energy lost during the collision is .
