Smoking Is Responsible for What Percentage of Lung Cancer

question 147

Multiple Choice

Smoking is responsible for what percentage of lung cancer?

• A)55 percent
• B)72 percent
• C)85 percent
• D)100 percent

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Definitions:

Mass Extinctions

Events in Earth's history when significant numbers of species disappear rapidly and irreversibly, often due to drastic environmental changes.

Varves

Thin, alternating light-colored and dark layers of sediment that form in lakes because of seasonal variations of deposition and biologic activity.

Ice Cores

Cylinder-shaped samples from ice sheets or glaciers that scientists study to understand past climates.

Tree Rings

The concentric rings on the cross-section of a tree trunk, representing a record of a tree's age and the conditions under which it grew.