Solve the Problem $\mathrm { N }$ That Will Survive $x$ Hours Is Modeled by the Formula

question 234

Multiple Choice

Solve the problem.
-For a culture of 70,000 bacteria of a certain strain, the number of bacteria $\mathrm { N }$ that will survive $x$ hours is modeled by the formula $\mathrm { N } = 7000 \sqrt { 100 - \mathrm { x } }$ . After how many hours will 21,000 bacteria survive?

• A) \(91 \mathrm { hr }\)
• B) \(97 \mathrm { hr }\)
• C) \(79 \mathrm { hr }\)
• D) \(9 \mathrm { hr }\)

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Definitions:

Low-Frequency Sounds

Sounds that have a low pitch, typically considered to be below 250 Hz, and can range from deeper tones to vibrations.

Brain Regions

Specific areas within the brain, each responsible for different functions, such as memory, emotion, sensory processing, and motor control.

Basilar Membrane

A critical structure within the cochlea of the inner ear, playing a key role in the process of hearing by separating two liquid-filled chambers and contributing to sound wave analysis.

High-Frequency Sounds

Sounds that have a high pitch, usually measured in hertz (Hz), and often are above the upper limit of human hearing.