Nitrogen fixation is the conversion of nitrogen gas into ammonia. Please select TWO answers of how this can occur: A)air on top of the top layer of soil comes in contact with particular types of nitrogen-fixing bacteria

B)overflow of water within the soil

C)man-made fertilizers on farm fields exceed natural nitrogen levels in the soil and kill all the bacteria

D) by the intense energy of a lightening strike

Read the following scenario to answer the following question. in some zoos, rare crosses between a male lion and a female tiger have produced hybrid offspring called "ligers." male ligers are sterile but some female ligers are fertile. in the wild, lion and tiger ranges do not naturally overlap, making such a cross unlikely. furthermore, the solitary behavior of tigers and the social organizations of lions create behavioral differences. applying the biological species concept, the sterility of ligers reveals that a. lions are probably a subspecies of tigers b. tigers and lions are the same species c. a new species called "ligers" is forming d. tigers and lions are separate species

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

Astudent completed a lab report. which correctly describes the difference between the “question” and “hypothesis” sections of her report? “question” states what she is asking, and “hypothesis” states the result of her experiment. “question” states what she is asking, and “hypothesis” states what she thinks the answer to that question is in “if . . then . . because” format. “question” describes what she is trying to find out, and "hypothesis" states the procedures and methods of data collection. “question” describes what she is trying to find out, and “hypothesis” states any additional information or prior knowledge about the question.