Multiple Choice
Which of the following is not a source of human- fixed nitrogen?
A) irrigation agriculture
B) industrially produced fertilizers
C) combustion of fossil fuels
D) cultivation of soybeans
Correct Answer:

Verified
Correct Answer:
Verified
Q14: Use the following graph and information to
Q15: <img src="https://d2lvgg3v3hfg70.cloudfront.net/TB6548/.jpg" alt=" Figure 53.9 -Upon
Q16: What is the main reason for using
Q17: Which statement best describes what ultimately happens
Q18: Which of the following is a consequence
Q20: Considering the global carbon cycle, where are
Q21: <img src="https://d2lvgg3v3hfg70.cloudfront.net/TB6548/.jpg" alt=" Figure 53.7 -Considering
Q22: <img src="https://d2lvgg3v3hfg70.cloudfront.net/TB6548/.jpg" alt=" Figure 53.3 -Which
Q23: What do researchers typically focus on when
Q24: <img src="https://d2lvgg3v3hfg70.cloudfront.net/TB6548/.jpg" alt=" Figure 53.3 -Which