Answer: 
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
A double displacement reaction in which one of the product is formed as a solid is called as precipitation reaction.
The balanced chemical equation is:

I believe the answer is thermal expansion.
Answer:the parts of the body which is nearest to the ground ie thier back will show discoloration
Explanation:
If the body remains at a position for long hours, the parts of the body which is nearest to the ground can develop a skin discoloration as a result of pooling of blood in the tissues and this is called livor mortis, which tends to be permanent from 8Hours upwards.
Answer:
If you touch the knob of a positively charged electroscope with another positively charged object,the leaves of the electroscope would remain apart.
The answer is so you do not overheat