The number of species from the following carrying a single lone pair on central atom Xenon is ___________.

$$\mathrm{XeF}_{5}^{+}, \mathrm{XeO}_{3}, \mathrm{XeO}_{2} \mathrm{~F}_{2}, \mathrm{XeF}_{5}^{-}, \mathrm{XeO}_{3} \mathrm{~F}_{2}, \mathrm{XeOF}_{4}, \mathrm{XeF}_{4}$$

The number of following factors which affect the percent covalent character of the ionic bond is _________

(A) Polarising power of cation

(B) Extent of distortion of anion

(C) Polarisability of the anion

(D) Polarising power of anion

The number of species having a square planar shape from the following is __________.

$$\mathrm{XeF}_{4}, \mathrm{SF}_{4}, \mathrm{SiF}_{4}, \mathrm{BF}_{4}^{-}, \mathrm{BrF}_{4}^{-},\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\right]^{2+},\left[\mathrm{FeCl}_{4}\right]^{2-},\left[\mathrm{PtCl}_{4}\right]^{2-}$$

In an ice crystal, each water molecule is hydrogen bonded to ____________ neighbouring molecules.