An Increase About 1,000 Years Ago in ¹³C Content of Human

question 13

Multiple Choice

An increase about 1,000 years ago in ¹³C content of human collagen from archeological sites in eastern North America probably records

• A) replacement of vegetables and grains in the diet by meat.
• B) replacement of corn by beans and squash in the diet.
• C) increasing consumption of corn.
• D) increasing levels of ¹³C in soils.
• E) increasing levels of ¹³C in the atmosphere.

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Definitions:

Bonds

Financial instruments representing loans made by an investor to a borrower, typically corporate or governmental, which must be paid back with interest.

Positive Integers

Whole numbers greater than zero, found to the right of zero on the number line.

Difference

The result of subtracting one number from another to show the gap or distance between them.

Substitution

A method used in algebra and calculus involving replacing a variable with its corresponding value or another expression to simplify or solve an equation.