regular grammar

Question

Consider the following regular expressions
i) (a/b)*
ii) (a*/b*)*
iii) ((ε / a)b*)*
Which of the following equal?

Answer 1

Only option 1 & 2 are equal

option 1) (a+b)^*

option 2) (a*+b*)* = (a+b)*

option 3) ((epsilon+a)b*)*=(ab*)*