Coesider the function

$f(x,y)=e^{\frac{x}{4}}cos(y)$

$($a$)$ Consider the cross$-$section of $f(x,y)$ at $x=0.$ Find and graph this $1-$variable function. $($Be sure to label your axes'$)$

$($b$)$ Find the slope of the tangent at $y=\frac{}{4}$ to the fusction you found in $($a$).$

$($c$)$ Express your anwer to $($b$)$ in terms of partial derivatives and check that it agress with $($b$).$