Explain seven (7) chemical barrier of the natural antimicrobial substances in the human body​

Grasses--> mice--> cats--> coyotes suppose 10,000 units of energy are available at the level of the grasses. what is the total number of energy units lost by the time energy reaches the coyote?

Which of the following is the earliest era of earth's geologic time scale? cenozoic mesozoic precambrian paleozoic

Why are some people more concerned about shark survival than about shark attacks?