$A$ frog,which feeds on insects,is a

If plants (producers) of an ecosystem die,then the system

Read the following statements carefully and answer the question given below:
$(1)$ $NPP = GPP - R$
$(2)$ Productivity of an ecosystem can be measured in $g/m^2/yr$ or $kcal/m^2/day$.
$(3)$ The total amount of energy produced by all producers in an ecosystem is called Gross Primary Productivity $(GPP)$.
$(4)$ The net primary productivity of the oceans is $55$ billion tons.
State the number of correct statements.

Which of the following statements is incorrect?

Whale is

Which one of the following is not a function of an ecosystem?