Let $g(x,y)=cos(x5y).$

$($a$)$ Evaluate $g(10,-2).$

$g(10,-2)=$

$($b$)$ Find the domain of $g.$

$-1x1,-\frac{1}{5}y\frac{1}{5}$

$-\frac{}{2}x5y\frac{}{2}$

$R^2$

$-1x5y1$

$-5x5,-1y1$

$($c$)$ Find the range of $g.($Enter your answer using interval notation.$)$