For each of the following regular grammars, give a regular expression for the language generated by the grammar.

a$)$

$SaA$

$AaA|bA|b$

c$)$

$SaS|bA|$

$AbB$

$BaB||$

d$)$

$SaS|bA|$

$AaA|bS|$

b$)$

$SaA$

$AaA|bB|$

$BbB||$