Question

A=(1,2,5,7,8)
B=(5,9,10,12)
How many subset does set B have.

Answer 1

`n(B)=4 \Rightarrow P(B)=2^4=16`


`A\cup B=\{1,2,5,7,8,9,10,12\}\\ n(A\cup B)=8`