Answer: Option (d) is the correct answer.
Explanation:
In winter's, temperature of atmosphere is low and due to this molecules of air present in the tire come closer to each other as they gain potential energy and loses kinetic energy.
Hence, air pressure decreases and there is need to fill more air in the tire.
Whereas is summer's, temperature is high so, molecules of air inside the tire gain kinetic energy and move rapidly from one place to another due to number of collisions. So, air pressure increases and there is no need to fill more air inside the tire.
Thus, we can conclude that the temperature is lower, so the air inside the tires contracts.
Answer:
Initially
of nitrogen dioxide were in the container .
Explanation:
Volume of the container at low pressure and at room temperature =
Number of moles in the container = 
After more addition of nitrogen gas at the same pressure and temperature.
Volume of the container after addition = 
Number of moles in the container after addition=
Applying Avogadro's law:
(at constant pressure and temperature)



Initially
of nitrogen dioxide were in the container .
Given :
An atom of a certain element has 12 protons, 14 neutrons, and 2 valence electrons.
To Find :
The name of this element.
Solution :
We know, element with atomic number ( number of protons ) 12 and valance electrons is Magnesium.
Now, isotope of magnesium of proton with 14 neutrons is Mg-16 .
Therefore, name of element is Mg-16 .
Hence, this is the required solution.