Which group of living organisms given below is a link in the food chain between green plants and a hawk?

Which of the following is responsible for the high biomass in an aquatic ecosystem?

Carbon constitutes . . . . . . of dry weight of organisms and . . . . . . percentage is dissolved in oceans out of total global carbon.

Find an incorrect statement for $DFC$ (Detritus Food Chain).

What changes are observed in energy at successive trophic levels in a food chain?

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.