13.Excluding purchases by businesses, the average
amount spent on a factory-new car has risen 30 per-
cent in the last five years. In the average household
budget, the proportion spent on car purchases has
remained unchanged in that period. Therefore the
average household budget must have increased by
30 percent over the last five years.
Which of the following is an assumption on which
the argument relies？
(A)The average number of factory-new cars pur-
chased per household has remained unchanged
over the last five years.
(B)The average amount spent per car by businesses
buying factory-new cars has risen 30 percent in
the last five years.
(C)The proportion of the average household budget
spent on all car-related expenses has remained
unchanged over the last five years.
(D)The proportion of the average household budget
spent on food and housing has remained
unchanged over the last five years.
(E)The total amount spent nationwide on factory-
new cars has increased by 30 percent over the
last five years.
3.Juries in criminal trials do not base verdicts on uncor-
roborated testimony given by any one witness. Rightly
so, because it is usually prudent to be highly skeptical
of unsubstantiated claims made by any one person.
But then, to be consistent, juries should end an all-
too-common practice: convicting defendants on the
basis of an uncorroborated full confession.
Which of the following, if true, most strengthens the
argument above?
(A) Juries often acquit in cases in which a defendant
retracts a full confession made before trial.
(B) The process of jury selection is designed to screen
out people who have a firm opinion about the
defendant's guilt in advance of the trial.
(C) Defendants sometimes make full confessions when
they did in fact do what they are accused of
doing and have come to believe that the prose-
cutor has compelling proof of this.
(D) Highly suggestible people who are accused of
wrongdoing sometimes become so unsure of
their own recollection of the past that they can
come to accept the accusations made against
them.
(E) Many people believe that juries should not con-
vict defendants who have not made a full con-
fession.