A Random Sample of 79 Companies from the Forbes 500

question 48

Multiple Choice

A random sample of 79 companies from the Forbes 500 list (which actually consists of nearly 800 companies) was selected,and the relationship between sales (in hundreds of thousands of dollars) and profits (in hundreds of thousands of dollars) was investigated by regression.The following results were obtained from statistical software. Is there strong evidence of a straight-line relationship between sales and profits? Explain briefly.

• A)Yes,because the slope of the least-squares line is positive
• B)Yes,because the P-value for testing if the slope is zero is quite small
• C)No,because the value of the square of the correlation is relatively small
• D)It is impossible to say because we are not given the actual value of the correlation.

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Definitions:

Organic Monomers

Small organic molecules that can chemically bind to other molecules to form polymers, essential in the structures of life.

Clay

A natural, earthy material known for its plasticity when wet, used in ceramics and as a key component of soil.

Vascular Plants

Plants that have specialized structures for the transport of water and nutrients, including xylem and phloem.

Silurian Period

A geologic period and system that extends from about 443.8 million to 419.2 million years ago, noted for significant biological developments including the appearance of the first clearly identifiable land plants.