The pyramid of number in a grassland ecosystem is

Consider the following statements about ecological pyramids

$I.$ Charles Elton developed the concept of ecological pyramid

$II.$ After the name these pyramids are also called as Eltonian pyramids

$III.$ It is a graphical representation or pyramid shaped diagram which depicts the number of organisms, biomass and energy at each trophic level

Which of the statements given above are correct?

Given below is the diagram of the ecological pyramids

This type represents

Which one of the following is not used for construction of ecological pyramids ?

Write a short note on pyramid of numbers and pyramid of biomass.

If producer is a large tree that supports a number of herbivorous animals which are further attacked by ectoparasites, the pyramid of number shall be