Which of the following molecules has unequal bond lengths?

The shape of a molecule depends on which factor?

Which one has $sp^2$ hybridisation?

The number of species from the following in which the central atom uses $sp^3$ hybrid orbitals in its bonding is . . . . . . .
$NH_3, SO_2, SiO_2, BeCl_2, CO_2, H_2O, CH_4, BF_3$

The hybridisation of the central atom $I$ in $IF_7$ is:

Which of the following is true for the geometry of different nitrogen atoms $(N)$ present in histamine as labeled in the structure?