Answer:
It would be 14 because since each book is 3.5cm thick times that by 4 and get 14.
Step-by-step explanation:
Given

Hope it will help :)❤
10^11 is 100,000,000,000
10^3 is 1000
1,10,100,1000,10000,100000,1000000,100000000,100000000000.
I think it might be 4 times bigger