A Study of Drug Addicts in Amsterdam Recorded How Often

question 30

Multiple Choice

A study of drug addicts in Amsterdam recorded how often each addict had recently injected drugs and whether or not the addict was infected with HIV, the virus that causes AIDS. Here is a two-way table of the numbers of addicts in each condition:

The chi-square statistic for this table has how many degrees of freedom?

• A) 1
• B) 2
• C) 3
• D) 4
• E) 6

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Definitions:

Diester

A diester is an organic compound formed when two hydroxyl groups in an acid are replaced by ester groups.

Vulcanization

A chemical process for converting natural rubber or related polymers into more durable materials via the addition of sulfur or other equivalent curatives or accelerators.

Synthetic Rubber

A man-made elastomer designed to mimic natural rubber, noted for its elasticity and produced through polymerization processes.

Saran

A synthetic polymer known for its barrier properties, particularly for preventing the passage of water vapor; used in food wrap and various coatings.