I believe it goes as the following::
1) Waves transfer energy without moving particles
2) The two types of waves are longitudinal and transverse waves OR The two types of waves are mechanical and electromagnetic waves. Both are applicable and should be correct!
Explanation:
Principle focus is the point on the axis of a convex lens, where the parallel rays of light from one side of the lens. meet on other side after refraction. Distance between optical centre to principle focus point is the focal length.
Answer:

Explanation:
As we know that volume is given as

so it is given in liter as

now we have six pack of such volume
so total volume is given as


so its mass is given as

now the change in temperature is given as


now the heat given to the liquid is given as




The only balanced equation is B. If you look at the equation and break it down you can see that in:

→

Starting from the left side of the equation there are 2 Nitrogen atoms, and 2 oxygen atoms as indicated by the subscript.
To balance the equation, the number of atoms of each element in the right side equation should be equal to left. By putting the numerical coefficient of 2, you will distribute that to each element. So you will end up with 2 nitrogen atoms and 2 oxygen atoms on the left side of the equation. Thus, the equation is balanced.
The answer again, is B.
<span>Kinetic energy increases and potential energy decreases.
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