Mechanical Waves require a medium to travel through in order to transport their energy from one location to another.
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The molarity remains the same so the ratio does not change
Answer:
c. natural force or pull toward the earth
Explanation:
Gravity of the earth is the force of attraction that it naturally possesses to attract any mass.
An apple falls on the earth due to this force of gravity.
The force of gravity near to the surface of the earth is given as:
where:
m= mass of the body
g= acceleration due to gravity
The variation of the gravitational force with height is given as:

where:

where
R = radius of the earth 
Answer:
See the explanation below.
Explanation:
If you connect the three bulbs 20 W each will have a total power of 60W.
Now we need to understand to assign the meaning of the word gap, that is, if the circuit is open at that point or if there is no bulb connected at that point.
If the circuit is open at Point 2, there will be no current in the circuit, so the battery will drain faster with the three bulbs 20W.
In the second event, where gap means that there are no bulbs connected at that point, it means that you have two bulbs connected in series of 80W each.
In this case the bulbs will consume 160W thus drain the battery faster than the three 20W bulbs connected in series.