Argument evaluation situation most of the employees

Argument Evaluation
Situation Most of the employees of the Haglut Corporation work in the
manufacturing division, where employees average 14 hours per
month in overtime. The average amount of overtime per month for
employees at Haglut does not fluctuate much from month to
month.
Reasoning What is the argument’s greatest weakness? The argument’s
conclusion is that almost certainly each month most of the
employees of Haglut work at least some overtime. Answer choice
(D) identifies the argument’s greatest weakness because it points
out how the conclusion of the argument could be false even if all of
the supporting information were true. For example, it could be that
less than half of the employees work any overtime at all, but those
that do work overtime work much more than 14 hours per month.
A The argument leaves open the possibility that in some divisions of the
corporation, the average monthly overtime of its employees is quite
different from 14 hours, even if (as the argument states) that average does
not change much from month to month.
B The argument does not assume that there is a monthly amount of
overtime worked by each employee of the manufacturing division
equivalent to the company-wide average monthly overtime per employee.
C This does not identify a weakness that can be detected in the argument.
Since the claims mentioned here are not specified, the passage provides no
evidence that clearly indicates that this type of confusion is playing a role in
the argument.
D Correct. The argument ignores the possibility that most of the
employees of Haglut work no overtime at all in a particular month—which is
quite consistent with the argument’s assertion that the average number of
monthly overtime hours per employee within the manufacturing division is
14.
E The possibility described by this is not overlooked by the argument,
because this possibility is consistent with the conclusion. It could easily be
that most employees of the corporation work some overtime each month—
as the conclusion envisions—but that there are always some employees who
do not work any overtime.
The correct answer is D.

89. In the past the country of Malvernia has relied heavily on imported oil. Malvernia
recently implemented a program to convert heating systems from oil to natural
gas. Malvernia currently produces more natural gas each year than it uses, and oil
production in Malvernian oil fields is increasing at a steady pace. If these trends in
fuel production and usage continue, therefore, Malvernian reliance on foreign
sources for fuel is likely to decline soon.
Which of the following would it be most useful to establish in evaluating the
argument?
(A) When, if ever, will production of oil in Malvernia outstrip production of
natural gas?