$a)$

${65}^o+\alpha =180{°}^o$  

$\beta =\alpha ={180}^o-{65}^o={115}^o$ $\beta =\alpha ={180}^o-{65}^o={115}^o$  

$\gamma ={65}^o$  

$b)$  

$\gamma ={110}^o$  

$\alpha =\beta ={180}^o-{110}^o={70}^o$  

$c)$  

$45°+\delta ={180}^o$  

$\delta ={180}^o-{45}^o={135}^o$  

$\delta =\gamma$  

$\alpha =\beta =180{°}^o-{135}^o={45}^o$