In a Hearing Test, Randomly Selected Subjects Estimate the Loudness

question 12

Multiple Choice

In a hearing test, randomly selected subjects estimate the loudness (in decibels) of a sound, and the results are (mean = 70) : 68, 67, 70, 71, 68, 75, 68, 62, 80, 73, 68. What is the standard deviation?

• A) 18
• B) 4.73
• C) 22.40
• D) 324
• E) 6.76

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Definitions:

Pyroclastic Flow

A fast-moving current of hot gas and volcanic materials that flows down the side of a volcano during an explosive eruption.

Sandstone

A sedimentary rock consisting of sand-sized mineral particles or rock fragments.

Basaltic Lava

A type of magma or lava that is low in silica and has a relatively low viscosity, leading to smoother flow characteristics.

Obsidian/Glass

A natural volcanic glass formed from the rapid cooling of acidic lava, known for its conchoidal fracture and sharp edges.