What are the formal charge on each oxygen atom and the $P-O$ bond order in the $PO_4^{3-}$ ion,respectively?

Which of the statements given below is incorrect?

The strongest $P-O$ bond is found in the molecule

Which of the following is the correct decreasing order of bond angles?

The numbers of lone pairs and bond pairs in hydrazine are,respectively

Fill in the blanks given below:
$(i)$ The two theories based on the principles of quantum mechanics are ........ and ......... .
$(ii)$ The electronic configuration of carbon in the excited state is ........... .
$(iii)$ Through the combination of atomic orbitals,....... are formed.
$(iv)$ The ${\rm{CH}}_4$ molecule has a .......... shape.