In the figure,if $AB \parallel DE$,$\angle BAC = 35^o$ and $\angle CDE = 53^o$,find $\angle DCE$. (in $^o$)

In the figure,find the values of $x$ and $y$ and then show that $AB \parallel CD$.

In the figure,$OP$,$OQ$,$OR$,and $OS$ are four rays. Prove that $\angle POQ + \angle QOR + \angle SOR + \angle POS = 360^o$.

In the figure,if $AB \parallel CD$,$CD \parallel EF$ and $y: z = 3: 7$,find $x$. (in $^o$)

In the figure,ray $OS$ stands on a line $POQ$. Ray $OR$ and ray $OT$ are angle bisectors of $\angle POS$ and $\angle SOQ$,respectively. If $\angle POS = x$,find $\angle ROT$. (in $^o$)

In the figure,lines $AB$ and $CD$ intersect at $O$. If $\angle AOC + \angle BOE = 70^o$ and $\angle BOD = 40^o$,find $\angle BOE$ and reflex $\angle COE$.