6. A certain fossil is 75% decayed, if half the carbon 14 breaks down every 5730 years to form nitrogen 14, how old is the fossil?

A. 8595 years C. 133250 years

B. 10460 years D. 171907 years
7. The structures are similar because they evolved to do the same job, not because they were inherited from a common ancestor. Which pair of animals have an analogous structure?

A. Wings of birds and bats

B. Flippers of whale and forelimb of cat

C. Wings of butterfly and arms of human

D. Wings of birds and fingers of the human

8. Each certain area has a different carrying capacity. What will happen if the population is beyond their carrying capacity?

A. They will reproduce.

B. They will continue to grow.

C. They will increase in number.

D. They will decrease in the number.

9. The earth’s biodiversity is in grave danger. In the present era, human beings are the most dangerous cause of the destruction of the earth’s biodiversity. Which of the following statement BEST defines biodiversity?

A. It pertains to the richness of lives on earth forming biosphere.

B. It pertains to all the different kinds of life you’ll find in one area.

C. It is the variety of animals, plants, fungi, and even microorganisms like bacteria that make up our natural world.

D. All of the answers are correct.

10. Extinction happens when environmental factors or evolutionary problems cause a species to die out. Which of the following is the worst culprit when it comes to
activities threatening species with extinction?

A. Chemical pollutants C. Overharvesting

B. Habitat destruction D. Disease​