Mack Trucks Decides to Conduct an Experiment to Determine If

question 68

Multiple Choice

Mack Trucks decides to conduct an experiment to determine if a new oil additive actually results in increased fuel efficiency.They find a lab that contains 50 engines that are exactly alike.Mack randomly divides the 50 engines into two groups - an experimental group (which has the new oil additive) and the control group (which does not have the new oil additive) .They pour the exact same amount of fuel into all 50 engines and time how long each engine runs.Afterward,they average the length of time run by the 25 engines in the control group versus the 25 engines in the experimental group.Which of the following represents the experimental design in this study?

• A)X O1
• B)(R)O1 X O2 (R)O3 O4
• C)O1 X O2
• D)(R)O1 X O2 (R)O3 D O4
• E)(R)O1 O2 (R)O3 D O4

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Definitions:

River Zone

The area or region surrounding a river, including its banks and adjacent land, which can play critical roles in ecosystem function and biodiversity.

Source Zone

The specific location or area where pollutants originate and from which contamination spreads to surrounding environments.

Transition Zone

An area or region where two or more distinct habitats or ecosystems meet and integrate, often rich in species diversity.

Inland Freshwater Wetland

Wetlands located away from coastal areas, characterized by fresh water and supporting diverse plant and animal life, important for flood control and water purification.