Proper set

Q.

What is the differentiation of $1$?

Q. Set of natural numbers A = $A=\{x:xϵN\}$ is a proper subset of which of the following

1. Set of whole numbers $A_1=\{x:xϵW\}$
2. Set of Real numbers $A_2=\{x:xϵR\}$
3. Set of Integers $A_3=\{x:xϵI\}$
4. All of the above.

Q.

The number of proper subsets of the set $\{1,2,3\}$ is ___.

1. 8

2. 7

3. 6

4. 5