Using a Standard Treadmill Test, I Observe That Today's 30-Year-Olds

question 9

Multiple Choice

Using a standard treadmill test, I observe that today's 30-year-olds are more aerobically fit than are today's 60-year-olds. Which of the following is the LEAST plausible explanation of this observation?

• A) Fitness is more highly valued in today's society, so the younger cohort exercises more regularly than the older cohort does now or did when they were 30.
• B) In U.S. society, jobs and lifestyles become more and more sedentary as adults get older. The observed difference thus reflects a genuine change with age, but not an inevitable one.
• C) Inevitable physical changes associated with basic biological aging lie behind the observed difference.
• D) It is more difficult to test the aerobic capacity of 60-year-olds, so the findings are probably misleading.

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Definitions:

Variable Manufacturing Overhead

Costs in the manufacturing process that vary with production volume, including costs related to supplies and utilities directly involved in production.

Direct Labor-Hours

The total hours worked directly on manufacturing goods or providing services, often used to allocate labor costs to products or services.

Manufacturing Overhead

Expenses related to the manufacturing process that are not directly attributed to individual units produced, such as maintenance and factory supervision.

Machine-Hours

A measure of the time a machine is operated, used as a basis for allocating manufacturing overhead in some costing systems.