<u>Velocity = 27.2 m/s</u>
<u>Explanation:</u>
The velocity at the bottom of the first hill can be determined with the change in Kinetic energy. Due to energy conversion, both the change in kinetic energy and potential energy is same when the height is changed.
So, by applying the formulas:
KE = 
where KE is Kinetic energy, m is the mass and v is the Velocity.
PE = mgh
where PE is Potential energy, m is the mass, g is the gravitational force and h is the height.
Since, both the energies are equal, we can write:
PE = KE
= mgh
v² = 2gh
v = 
To Substitute:
h = 42 - 4.2 = 37.8 m
g = 9.8 m/s²
So, v = 
= 27.2 m/s
Having different densities being swirled rapidly will cause sedimentation. Sedimentation is the segmentation of the mixture creating layers of particles of these different densities. The process of rapid swirling is called differential centrifugation. An example use of this method is separation human blood into, red, platelet and white blood cells.
<span>C. the slope of that objects velocity-time graph
Hope it helps!
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Chiefly in science fiction) an invisible barrier of exerted strength or impetus.
<span>The first response would be "deca," since this is a multiple of 10^1. B, since it's working off the thousands prefix (10^3), would be "kilo." The third, at 10^-6, would be "micro." Next, at 10^-9, would be "nano," and the final, 10^18, would have a prefix of "exa."</span>
