In chapter 27 of To Kill A Mockingbird, what three things does Bob Ewell do that alarm Aunt Alexandra?

In To Kill A Mockingbird, it seems
that the residents of Maycomb County do not learn from their own mistakes. Tom Robinson,
an innocent man, has been tried and convicted and is dead. Scout, the narrator,
recalling the events, recognizes the hypocrisy of the locals and asks Jem in chapter 26
how it is possible to "hate Hitler so bad an' then turn around and be ugly about folks
right at home?" She has learned from her father, Atticus, not to judge others and yet
she sees people being unnecessarily unkind. Atticus hopes she understands from
everything that he has taught her that people have "blind spots" which prevent them from
being rational and fair. She knows that she should not judge them however because as
early as chapter 3, Atticus told her that "You never really understand a person until
you consider things from his point of view." It seems the Maycomb residents do not share
this opinion or Atticus's integrity. 

Bob Ewell is
Mayella's father and is a poor role model. He does not care for his children and it is
his apparent beating of Mayella that started the tragic turn of events and led to Tom's
death after Tom had felt sorry for Mayella and been blamed for her assault and accused
of rape. In chapter 27 Bob Ewell has been given a job by the WPA (the Works Progress
Administration), an organization set up to ease unemployment and to help the otherwise
jobless perform functional tasks and works. His enthusiasm is short-lived and it is
significant and ironic that he loses a job created to help him and people like him. He
lasts less than a week and blames everyone else and especially Atticus for his
misfortune. 

Another significant occurrence is how Judge
Taylor deals with a prowler at his home one Sunday night. Presumably the would-be
burglar thought no one was home. The judge takes it in his stride but sits with his
shotgun across his lap. He does not get a good look at the "visitor" but seems
unperturbed. He is certainly prepared to act against the intruder who is assumed to be
Bob Ewell.  

Scout also tells the reader how Maycomb
residents soon forgot about Tom Robinson and Bob Ewell and even Boo Radley. Tom's
employer (Link Deas) however gives Tom's widow a job even though he doesn't really need
her assistance. Bob Ewell makes Helen Robinson feel afraid as he follows her and berates
her and it is necessary for Mr. Link Deas to intervene on her
behalf.

It is Bob Ewell's behavior which alarms Aunt
Alexandra. He loses his job and blames Atticus. He sneaks around at the Judge's home in
the dark and he threatens Tom's widow Helen. It seems that even though his daughter won
in court, he holds a grudge against the people who tried to do the right thing. He is
apparently bitter because, as Atticus points out to Aunt Alexandra, "He thought he’d be
a hero, but all he got for his pain was… was, okay, we’ll convict this Negro but get
back to your dump."