12. How does the article conclude? O A The author restates the opportunity
Halloween provides to study human
behavior.
OB The author includes other holidays that
provide opportunities to study human
nature.
OC The author encourages kids to not let
candy or other influences sway their
decisions.
OD The author claims that kids' behavior
differs on Halloween from how they
normally act.

11 d

12 a

13 d

14 b

explanation:

21 balloons is the story of professor william sherman's travels.

in 1883, he set off from san francisco for a balloon ride over the pacific and was found a month later floating with 21 balloons in the atlantic ocean. this seemed an astounding feat and everyone wanted to know what had happened.    

professor sherman was loyal, however, and said he would tell his tale first to the western american explorers club in san francisco, of which he was a member. this built up suspense for several chapters before he began to tell of the wonders of his adventures and the amazing island of krakatoa, an island which had just been blown up by a volcano.  

the residents of krakatoa are all millionaires who live under a "gourmet government" of their own devising. we get to see all the incredible adventures that creative people with unlimited resources would create according to the author.