How can I make yes/no questions is a batch file?

mplayer.exe  -cache 1024  -speed 1.66  %1
SET /P ANSWER=Do you want to delete %1 file (Y/N)?
echo You chose: %ANSWER%
if /i {%ANSWER%}=={y} (goto :yes)
if /i {%ANSWER%}=={yes} (goto :yes)
goto :no
:yes
rm -f %1
exit /b 0
:no
echo file wasn't deleted  
exit /b 1

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