$a)\alpha ={180}^o-\left({27}^o+{33}^o\right)={180}^o-{60}^o={120}^o$

$\beta ={27}^o+{33}^o={60}^o$

$b)\alpha ={90}^o+{37}^o={127}^o$

$\beta ={180}^o-{127}^o={53}^o$

$c)\alpha ={180}^o-{50}^o={130}^o$

$\beta ={50}^o$