そりゃあ

Etymology 1
Contraction of either or  with the topic marking particle.

Pronoun

 * 1)  that's
 * 2)  he, she, that
 * 1)  he, she, that

Etymology 2
Contraction of and auxiliary verb  or variant such as  or.

Adverb

 * 1)  certainly, of course, well
 * 2)  just like that, right
 * 1)  just like that, right