1 Arrange the following time periods from oldest to youngest

1. Arrange the following time periods from oldest to youngest.

Cenozoic, Hadean, Ordovician, Triassic..

2. Which represents a longer period of time?

a.From the first appearance of vertebrates until the extinction of the dinosaurs

b.From the extinction of the dinosaurs until the appearance of Homo sapiens

Solution

1. ANS:

Time periods from oldest to youngest

Cenozoic      - 65 0 Million years (Present Time) Youngest

Triassic         - 213 248 Million years

Ordovician     - 435 492 Million years

Hadean         - 4500 – 4000 Million years oldest

2. ANS: a. From the first appearance of vertebrates until the extinction of the dinosaurs.

Explanation:

From the first appearance of vertebrates until the extinction of the dinosaurs took several 100’s of million years.

From the (Jurassic time) dinosaur’s time to until the appearance of Homo sapiens took just 200 million years only.