The answer to number 2 is ' as the price of a good rises...products' and the answer to number 3 is Calculator and Cell Phone.
Addict is word for using too much drugs and not socializing with the world.
This is called the critical period.
The critical period itself is a stage of the development in the life of a human being in which is said that skills are most easily and most readily learned and acquired. This period usually varies for different things like binocular vision and language, but it is said that after the critical period the skills are acquired with much difficulty if they are to be acquired at all.