"Biomass" is the

They are autotrophic organisms.

In a pond ecosystem,benthos means

In a lake ecosystem,the rapid increase or explosion of a population is termed as:

$A$ farmer harvests his crop and expresses his harvest in three different ways.
$(a)$ $I$ have harvested $10$ quintals of wheat.
$(b)$ $I$ have harvested $10$ quintals of wheat today in one acre of land.
$(c)$ $I$ have harvested $10$ quintals of wheat in one acre of land,$6$ months after sowing.
Do the above statements mean one and the same thing? If your answer is yes,give reasons. If your answer is 'no',explain the meaning of each expression.

Name any two organisms which can occupy more than one trophic level in an ecosystem.