To Prevent the Tipping Point After Which Catastrophic Environmental Change

question 25

Multiple Choice

To prevent the tipping point after which catastrophic environmental change will happen,what needs to be done?

• A)Carbon dioxide emissions must be eliminated in the next two years.
• B)Global greenhouse gas levels must peak no higher than 450 ppm and start declining by 2015.
• C)All greenhouse gases need to immediately be reduced below their levels in 1990.
• D)Carbon dioxide emissions must not rise more than 800 ppm,double the levels in the atmosphere today.

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Definitions:

Nasal

Pertaining to the nose.

Vesicles

Small fluid-filled sacs in the body or on the cellular level, functioning in storage and transport.

Macules

Flat, distinct, discolored areas of skin that are not raised above the surrounding skin.

Lipid-soluble

The term lipid-soluble describes substances that can dissolve in fats and oils, allowing them to pass easily through cell membranes that consist of lipid bilayers.