If You Wanted to Test If Antibacterial Soap Worked Better

question 4

Multiple Choice

If you wanted to test if antibacterial soap worked better than regular soap, which experiment below has the strongest experimental design?

• A)Have people wash with antibacterial soap first and later with regular soap.
• B)Have two groups of people wash with either antibacterial or regular soap.
• C)Have two groups of people wash with either antibacterial or regular soap, without knowing which type of soap they are using.
• D)Have two groups of people wash with either antibacterial or regular soap, with neither the researchers nor the groups knowing which type of soap they are using.

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Definitions:

Bricklayers

Skilled workers who lay bricks to construct and repair walls, partitions, arches, and other structures.

Masonry Firm

A company specializing in the building and construction of structures using bricks, stone, concrete blocks, and other masonry materials.

Marginal Product

The extra production resulting from the use of an additional unit of a specific input, like labor or capital.

Productivity

The measure of the efficiency of production, often quantified as the ratio of output to inputs in the production process.