These Data, Derived from Ice Cores, Indicate That

question 15

Multiple Choice

These data, derived from ice cores, indicate that:

• A) temperatures and CO₂ concentration have remained constant until very recent inputs from humans
• B) several times in the past humans have perturbed the natural environment causing natural increases in CO₂ and temperature
• C) temperature increased, followed by an increase in CO₂
• D) all of these

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Definitions:

Placebo Group

A control group in an experiment that receives an inert treatment or substance (placebo) to compare against the effects of the active treatment on the experimental group.

Independent Random Samples

This term describes a statistical method in which each member of a set has an equal probability of being chosen, and the selection of one member is made without influencing the selection of any other member.

Significance Level

The threshold at which researchers decide whether an effect or result observed in data is statistically significant, commonly set at 0.05 or 5%.

Summary Statistics

Refers to a set of descriptive indices that summarize the central tendency, dispersion, and shape of a dataset distribution, including measures such as mean, median, variance, and standard deviation.