QuizMe

ישן

The economic value of world's ecosystem services to human beings, according to Constanza and his colleagues (1997), is:

		An average of US $ 16 trillion per year
		An average of US $ 54 trillion per year
		An average of US $ 33 trillion per year
		Cannot be evaluated

נערך Oct 22 '23 - 04:45

חדש

* השאלה נוספה בתאריך: 14-01-2023