With respect to air, water, and material resources, which of the ...

[cabate]

With respect to air, water, and material resources, which of the following is true?
 
  A) A forest is a closed system.
  B) A forest is an open system.
  C) A forest is an open system in terms of air, but closed in terms of material resources.
  D) A forest is an open system in terms of water, but closed in terms of energy resources.

Question 2

In terms of matter and resources, the Earth is essentially a(n) ________ system; In terms of energy, the Earth is a(n) ________ system.
 
  A) closed; closed
  B) closed; open
  C) open; open
  D) open; closed

[mjbamaung]

Answer to Question 1

B

Answer to Question 2

B

[cabate]

Excellent

[yeungji]

Thanks for the timely response, appreciate it