Question

Which of the following are true regarding geologic periods?

I. Periods are the longest intervals of geologic time.

II. A period may contain several epochs.

III. The Quaternary period is the period of present-day Earth.

IV. The Cambrian period is the last period of the Mesozoic era.

Answer 1

II and III only. The Cambrian Period is the first geological time period of the Paleozoic Era. And the longest unit in geological time is the supereon.