Doug Downey and His Colleagues Discovered That U

question 23

Multiple Choice

Doug Downey and his colleagues discovered that U.S.children spend what percentage of their waking hours in a given year in school?

• A)13 percent
• B)23 percent
• C)33 percent
• D)43 percent

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Definitions:

Bone Density

A measurement indicating the amount of mineral matter per square centimeter of bones, used in assessing osteoporosis and fracture risk.

Osteopenia

A condition characterized by lower than normal bone density, which can precede osteoporosis.

Osteomyelitis

An infection of bone, which can lead to bone damage and loss if untreated.

Periosteum

The dense layer of vascular connective tissue enveloping the bones except at the surfaces of the joints.