By the Year 2100, Lower Estimates of Atmospheric Carbon Dioxide

question 45

Multiple Choice

By the year 2100, lower estimates of atmospheric carbon dioxide concentrations are __________ parts per million.

• A)400
• B)450
• C)500
• D)550

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Definitions:

Colorfulness

The degree to which a visual stimulus is perceived as vivid or saturated, as opposed to dull or washed out.

Wavelength

The distance between successive crests of a wave, especially points in a sound wave or electromagnetic wave.

Pupil

The opening in the center of the iris of the eye that allows light to enter the retina.

Iris

The colored part of the eye that controls the size of the pupil and the amount of light that enters the eye.