Determine and Interpret Z-Scores
-A Severe Drought Affected Several Western $\begin{array} { l l l l l l l l l l l l l } 60 & 57 & 62 & 69 & 46 & 54 & 64 & 60 & 59 & 58 & 75 & 51 & 49 \end{array}$

question 153

Multiple Choice

Determine and Interpret z-Scores
-A severe drought affected several western states for 3 years. A Christmas tree farmer is worried about the drought s effect on the size of his trees. To decide whether the growth of the trees has been retarded, the farmer decides to take a sample of the heights of 25 trees and obtains the following results (recorded in inches) : $\begin{array} { l l l l l l l l l l l l l } 60 & 57 & 62 & 69 & 46 & 54 & 64 & 60 & 59 & 58 & 75 & 51 & 49 \end{array}$
$\begin{array} { l l l l l l l l l l l l } 60 & 57 & 62 & 69 & 46 & 54 & 64 & 60 & 59 & 58 & 75 & 51 \\ 67 & 65 & 44 & 58 & 55 & 48 & 62 & 63 & 73 & 52 & 55 & 50 \end{array}$
$\begin{array} { l l l l l l l l l l l l } 67 & 65 & 44 & 58 & 55 & 48 & 62 & 63 & 73 & 52 & 55 & 50 \end{array}$ The tree farmer feels the normal height of a tree that was unaffected by the drought would be 65 inches. Find the z-score for a tree that is 65 inches tall.

• A) \(z = 0.84\)
• B) \(z = 0.98\)
• C) \(z = 0.77\)
• D) \(z = 0.98\).

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Definitions:

GABA

A neurotransmitter in the brain that inhibits many of the activities of the central nervous system, thus playing a key role in reducing anxiety and stress.

Fatal Overdose

An excessive and lethal dose of a substance, typically drugs or medication, leading to death.

Heroin

Is an opioid drug made from morphine, a natural substance taken from the seed pod of various opium poppy plants, highly addictive and illegal.

Cocaine

A powerful stimulant drug derived from the leaves of the coca plant, known for its potential for addiction and abuse.