Logic subject-reductio ad absurdum

Question

Can you solve this using method reductio ad absurdum?

$\text{1})\ A ↔ (\neg B v C)$

$\neg A$

$\text{______________}$

$\neg B$

$\text{2})\ \neg(R∧ (S v T))$

$\text{3})\ R∧\neg T$

$S$

$\text{______________}$

$\neg R∧ S$