Problem $3(5$ points$).$ Classify the following attributes A$.$ discrete B$.$ continuous $(1)$ Time in term of AM or PM; $(1$ points$)(2)$ Brightness as measured by a light meter; $(1$ points$)(3)$ Social security number; $(1$ points$)(4)$ Height of the Westgate building; $(1$ points$)(5)$ Exam grade $($A$,$ B$,$ C$,$ D$,$ F$).(1$ points$)$ Problem $4(18$ points$).$ In a text data corpus, there are three documents