Answer:
mass of hydrogen in lake = 11.19% of 12
= 1.3428
check if question is correct or not
Explanation:
When sodium amide i.e.
reacts with water i.e.
results in the formation of sodium hydroxide i.e.
and ammonia
.
The chemical reaction is given by:

Now, when ammonia i.e.
reacts with water results in the formation of ammonium hydroxide i.e. 
The chemical reaction is given by:

Thus, the products of the above reactions are ammonia and ammonium hydroxide (without sodium ion).
The structures of the products are shown in figure (1): ammonium hydroxide and figure (2) ammonia.
Wait is that suppose to be a question??!!
Answer:
I think it will option B it will retain enough heat