The Annual Net Primary Productivity on land and ocean respectively are . . . . . . and . . . . . . billion tons.

The energy or biomass remaining after heterotrophic respiration is called ..........?

Given below are two statements:
Statement $I$: The primary source of energy in an ecosystem is solar energy.
Statement $II$: The rate of production of organic matter during photosynthesis in an ecosystem is called net primary productivity $\text{(NPP)}$.
In the light of the above statements,choose the most appropriate answer from the options given below:

Which of the following ecosystems has the highest productivity per unit area?

$A$: In secondary productivity,no new organic matter is formed.
$R$: It is only the utilisation of part of food manufactured by primary producers in the building of consumer biomass.

In an ecosystem,the rate at which organic molecules are synthesized from solar energy is known as: