Answer:
The reaction that takes place in an electro-chemical cell is the Redox reaction, a type of reversible reaction combining both oxidation and reduction reactions.
Answer:

Given: Mass of books = 6.5 kg
Mass of CD's = 1.5 kg
Mass of DVD's = 2.0 kg
Total mass = 6.5 kg + 1.5 kg + 2.0 kg = 10 kg


