The Rare Element Iridium Has Been Implicated in Which "Ancient

question 9

Multiple Choice

The rare element iridium has been implicated in which "ancient health" crisis?

• A) poisoning of primitive algae in the Hadean Eon
• B) disappearance of Neanderthal man during the early Cenozoic Era
• C) extinction of the woolly mammoths in late Pleistocene time
• D) extinction of the dinosaurs at the end of the Cretaceous Period

---

Definitions:

Normal Distribution

A bell-shaped distribution where data is symmetrically distributed around the mean, with most values clustering around a central region.

Normally Distributed

A balanced distribution of probability about the mean, showing a higher occurrence rate for data near the mean compared to data far away.

Standard Normal Distribution

A probability distribution that has a mean of zero and a standard deviation of one, used in hypothesis testing and other statistical analyses.

Z Scores

Scores that are normalized to show the number of standard deviations a data point is away from the distribution's average.