The power notation is used to represent multiple occurrences of a string. 

In this way 0³ will be equal with: 

∑={a,b,c,d}, w=ε

The length of w is:

A infinite sequence of symbols chosen from an alphabet is a string

The empty string e (or “epsilon”)  is the string with zero occurrences of symbols. 

  An alphabet is a finite, nonempty set of symbols.  

Choose the correct words that are generated by the given RE:

RE=(000)*1(10)*00

Choose the correct words that are generated by the given RE:

RE=a+ba*+bab

Choose the correct words that are generated by the given RE:

RE=0*(0+1)*11(11)*

For the given FA, the regular expression is:

RE(FA) = b(a+b)*ab*

For the given FA, the regular expression is:

RE(FA) = b(a+b)*ab*