It’s x200 plus 300 that’s why it is that answer
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Answer: 
Explanation:
a) 
: This is a non polar covalent compound which are held by weak vanderwaal forces of attraction.
b) 
: This is a covalent compound which is polar due to the presence of lone pair of electrons and are held by dipole-dipole forces of attraction.
c) : These are joined by a special type of dipole dipole attraction called as hydrogen bond. It forms between electronegative nitrogen atom and hydrogen atom and is the strongest interaction.
d) 
: This is a covalent compound and is non polar which are held by weak vanderwaal forces of attraction.
e) 
: This is a covalent compound and is non polar which are held by weak vander waal forces of attraction.
