How many species are known on the earth?

Given below are pie diagrams $A, B$ and $C$ related to the proportionate number of species of major taxa of invertebrates,vertebrates,and plants,respectively. Critically study and fill in the blanks $I, II, III$ and $IV$.

Match the following columns regarding the global species diversity of vertebrates and plants:

Column-$I$	Column-$II$
$(P)$ Birds	$(I)$ $12 \%$
$(Q)$ Mammals	$(II)$ $31 \%$
$(R)$ Amphibians	$(III)$ $23 \%$
$(S)$ Gymnosperms	$(IV)$ $32 \%$

According to Robert May's global estimates,what percentage of the total species on Earth has been discovered so far (in $\%$)?

How many genetically different varieties of mango occur in India (in $,000$)?

Number of endangered species of angiosperms in India is