The answer is #4. The first and second one involve acid, which is chemical weathering. The third one involves oxidation, which is a chemical process. The only mechanical process is option four.
The correct answer of the given question above would be option A. The purpose that the models served in ancient Egyptian and Chinese tomb is that, they were meant to make tombs more beautiful. These are wooden models which show ships, potters, servants and carpenters. Hope this answer helps.
Answer: A) nucleotide
Explanation: I too, am also in biology :)
Answer:
Answer is C. Bacteria
Certain types of bacteria have a relationship with certain plants where they help convert nitrogen into a usable form.
Explanation:
Nitrogen is abundant in the atmosphere, but plants cannot use it because of the absence of a necessary enzyme, nitrogenase, which converts nitrogen into a usable form. So they form a symbiotic relationship (mutually-beneficial arrangement) with nitrogen fixing soil bacteria (rhizobia) which perform biological nitrogen fixation. Biological nitrogen fixation is a process in which the symbiotic nitrogen-fixing bacteria coverts atmospheric nitrogen into ammonia and organic derivatives that plants can use to synthesize proteins. This bacteria form nodules on the roots of plants like legumes in which nitrogen fixation takes place.
Both plants and bacteria benefit from this symbiotic relationship, as the plant obtains ammonia to synthesize proteins from nitrogen in the atmosphere while bacteria obtain carbon compounds from the plant produced through photosynthesis and a secure environment to grow. As the plant roots leave behind some of the usable form of nitrogen in the soil, this process also increase soil fertility.