Exhibit 8-3
a Random Sample of 81 Automobiles Traveling on a Section

question 69

Multiple Choice

Exhibit 8-3
A random sample of 81 automobiles traveling on a section of an interstate showed an average speed of 60 mph. The distribution of speeds of all cars on this section of highway is normally distributed, with a standard deviation of 13.5 mph.
-Refer to Exhibit 8-3. If we are interested in determining an interval estimate for $\mu$ at 86.9% confidence, the z value to use is

• A)1.96
• B)1.31
• C)1.51
• D)2.00

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Definitions:

Hadrosaur

A type of duck-billed dinosaur that lived during the Late Cretaceous period, known for its flat beak and often elaborate head crests.

Crest

A prominent feature or projection on an animal's body, such as the plumage on the head of a bird or a ridge along a dinosaur's skull, often used for display or signaling.

Species Specific Sounds

Unique vocalizations or sound patterns that are characteristic of particular species, often used for communication.

Earliest Fossils

The oldest known remnants or impressions of ancient organisms preserved in rock.