A) 
The total energy of the system is equal to the maximum elastic potential energy, that is achieved when the displacement is equal to the amplitude (x=A):
(1)
where k is the spring constant.
The total energy, which is conserved, at any other point of the motion is the sum of elastic potential energy and kinetic energy:
(2)
where x is the displacement, m the mass, and v the speed.
We want to know the displacement x at which the elastic potential energy is 1/3 of the kinetic energy:
Using (2) we can rewrite this as
And using (1), we find
Substituting 
into the last equation, we find the value of x:
B) 
In this case, the kinetic energy is 1/10 of the total energy:
Since we have
we can write
And so we find:
If there is a large enough amount of water vapor in the air and the tempature is hot enough cloud or storms can form.
Answer:
What is a Pure Substance?
Explanation:
It is something which cannot be divided into parts by physical means, as it's all made up of the same thing. Pure substances are either elements or compounds. Elements can NOT be separated into other types of matter (physically or chemically).
1. For the first one if it doesn't shatter then it is hard.
2. We sould consider that room temperature is usuall<span>y from 18°C (64°F) to 23°C (73°F) and since the melting point of the substance is 40˚C the substance is liquid, because is melting point not an evaporation point it just melts from solid to liquid.
3. Well, in this one we have to consider that a chemical change it change the thing completely. So in this case is baking a cake because the products make the cake stop being them self and created something else.
4. It tends to have low reactivity. This is because viscosity means something like honey very sticky<span> ,</span> density is how hard it is and lastly the conductivity I would believe is to pass electricity or current.
5. It is a physical change because the evaporated water transforms again into water and then fall as rain, snow or ice.
Hope it helped <3</span>
Answer:
This example of the effect of volume on the pressure of a given amount of a confined gas is true in general. Decreasing the volume of a contained gas will increase its pressure, and increasing its volume will decrease its pressure.
Explanation:
Hope it helps
