You get back into your time machine with your wacky professor and take off again. as your time machine lands, you see an unusual landscape before you. as you open the door you realize you cannot breathe. you quickly shut the door, realizing you are in the:.
a. late precambrian
b. early mesozoic
c. early precambrian
d. late cenozoic

Option-C

Explanation:

The geological time scale represents the sequence of events that happened on Earth from the origin of Earth to the evolution of life till present.

The geological time scale is divided into time scales in which the longest time scale is represented as Eons which could last for billions of years.

The time period which was characterised by no oxygen is known as the Precambrian. The Precambrian refers to the time during which life originated which was present before the Cambrian period during which life evolved.

In the given question, if we land on the planet with no oxygen then we are present in the early Precambrian which represents the time of formation of life on Earth that is around 4.5 to 4.0 billion years ago.

Thus, Option-C is the correct answer.

the more fit you are, the faster the recovery. your heart rate drops most sharply in the first minute after you stop exercising; it should then fall about 20 beats a minute—a drop of less than 12 beats a minute is considered abnormal. this “recovery heart rate” is measured as part of an exercise stress test.

d would be your answer