The Spread of a Contaminant Is Increasing in a Circular $r ( t ) = 2.25 \sqrt { t }$

question 3

Multiple Choice

The spread of a contaminant is increasing in a circular pattern on the surface of a lake.The radius of the contaminant can be modeled by $r ( t ) = 2.25 \sqrt { t }$ ,where r is the radius in meters and t is the time in hours since contamination. ​
Find a function that gives the area A of the circular lake in terms of the time since the spread began.
​

• A) \(A \circ r ( t ) = 5.0625 \pi \sqrt { t }\)
• B) \(A \circ r ( t ) = 2.25 \pi t\)
• C) \(A \circ r ( t ) = 5.0625 t\)
• D) \(A \circ r ( t ) = 5.0625 \sqrt { t }\)
• E) \(A \circ r ( t ) = 5.0625 \pi t\)

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Definitions:

Normal Range

The range of values within which a physical or biochemical parameter is considered normal or typical for a healthy individual or system.

Renal Function

An assessment of how well the kidneys are working, often measured by the rate at which they filter waste products from the blood.

Elevated

A condition or object that is raised or lifted higher than the surrounding area or a normal level.

Creatinine

A waste product produced by muscles from the breakdown of a compound called creatine, commonly measured in blood or urine tests as an indicator of kidney function.