Answer: 
Energy is directly proportional to the frequency.
The energy of a photon is given by:
Where, E is the energy and 
is the frequency.
Frequency of the radio wave is given:
Multiply the above two:
Energy,
Hence, the energy of each photon of radio wave having frequency is 
Their different just put because their different
Option A: The air molecule moves from the girl's mouth to the ear of her friend
Answer:
A chemical reaction
Explanation:
In a physical change the chemical composition of a matter stays the same. One example is a change in state of matter. Consider water, you can heat it to vapour and cool it to form ice but you can get the exact same mass and colour after any physical change happens.
To form a two or more substance an internal arrangement of atoms must happen. For that chemical change should occur as only in chemical reactions atoms are rearrange to form new substances.
