If a primary producer has a gross primary productivity of 5000 kJ/m²/year and loses 1000 kJ/m²/year to respiration, what is the assimilated energy?

• A. 6000 kJ/m²/year
• B. 5000 kJ/m²/year
• C. 1000 kJ/m²/year
• D. 4000 kJ/m²/year

Answer: (D)