<span> The boiling point of water at sea level is 100 °C. At higher altitudes, the boiling point of water will be.....
a) higher, because the altitude is greater.
b) lower, because temperatures are lower.
c) the same, because water always boils at 100 °C.
d) higher, because there are fewer water molecules in the air.
==> e) lower, because the atmospheric pressure is lower.
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Water boils at a lower temperature on top of a mountain because there is less air pressure on the molecules.
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I hope this is helpful. </span>
Answer:
a) 
b) 
Explanation:
From the exercise we got the ball's equation of position:
a) To find the average velocity at the given time we need to use the following formula:
Being said that, we need to find the ball's position at t=2, t=2.5, t=2.1, t=2.01, t=2.001
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b) To find the instantaneous velocity we need to derivate the equation
If you'r referring to some objects, it means that the mass of the object is less than the water so it floats. If the mass of an object is greater than the mass of the water, it will sink. Compare it to a balloon, helium makes it rise, while normal air makes it sink.
