Answer:
"Growers using organic soils will never concern themselves with supplying oxygen to their plants; however, hydroponic growers like me must be well versed in the science of dissolved oxygen (from here on out called DO). While most crops seem to prefer about 9 PPM DO, some crops like lettuce have demonstrated little to no difference in fresh weight or dry weight when grown in DO levels ranging …"
Explanation:
Answer: B. all the nitrogen obtained by animals come from plants.
Explanation:
Animals are unable to use inorganic bacteria until plants absorb it and then animals get it from the plants so in effect, all the nitrogen obtained by animals comes from plants.
Plants absorb nitrogen in the form of Nitrates which were fixed by bacteria from Nitrites which were further fixed from Ammonium which was fixed from atmospheric Nitrogen all by bacteria.
Explanation:
Determining a substance's physical or chemical identity. What are the two main requirements for identification? The adoption of testing procedures that give characteristic results for specific standard materials and the number and type of tests needed to identify a substance to exclude all other substances.
Answer:
third and fourth trophic levels
Explanation:
D. Cross braces this is the right answer
