Changes in Life Expectancy in the Last Century Are Primarily

question 28

Multiple Choice

Changes in life expectancy in the last century are primarily due to:

• A)computers.
• B)reduced infant mortality.
• C)higher wages.
• D)better schools.
• E)improved nutrition.

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Definitions:

Like Terms

Terms in an algebraic expression that have the same variables raised to the same powers, allowing them to be combined through addition or subtraction.

Associative Property

A mathematical rule that states the way in which numbers are grouped (associated) does not change their sum or product.

Algebra

A branch of mathematics dealing with symbols and the rules for manipulating these symbols; it is a unifying thread of almost all of mathematics.

Distributive Property

A property that allows one to multiply a sum by a number by multiplying each addend individually by the number.