A) all mechanical waves need a medium to travel through.
This is true because mechanical waves move in a wave like manner at the atomic level. This is why an table vibrates when you put a speaker on top of it .
Answer:
Tug of War
An object sinking in water
Kicking a ball
In exothermic reactions, there is a release heat and the replacement of weak bonds with stronger ones.
<u>Answer:</u> The value of
for the given chemical reaction is 0.1415
<u>Explanation:</u>
Equilibrium constant in terms of partial pressure is defined as the ratio of partial pressures of the products and the reactants each raised to the power their stoichiometric ratios. It is expressed as 
For a general chemical reaction:

The expression for
is written as:

For the given chemical equation:

The expression for
for the following equation is:

We are given:

Putting values in above equation, we get:

The value of
for the given chemical reaction is 0.1415