Claro que yo no sabo como Hacer eso
Hiya
I don't see how this is a question, can you please elaborate a bit? Thanks!
Fixation
Nitrogen is converted from atmospheric nitrogen (N2) into usable forms, such as NO2-, in a process known as fixation. The majority of nitrogen is fixed by bacteria, most of which are symbiotic with plants. Recently fixed ammonia is then converted to biologically useful forms by specialized bacteria
Answer: It would probably be A.
Explanation: Abrasion means scraping or wearing away. Therefore the correct sample is probably going to look smaller, smoother, and more even from all the scraping of the river currents.
Hope that helps!