The ratio of number of lone pairs on central atom in ammonia, water and `XeF_(2)` are

Number of lone pairs are?

The number of lone pairs on central atom in XeF_2, XeF_4 and XeF_6 are:

Which have maximum number of lone pair on central atom :-

If number of lone pairs on central atom in XeF_(2), XeF_(4) and XeF_(6) are x, y, z. What is the sum of x+y+z here?

The total number of lone-pairs of electrons in melamine is.

Number of lone pairs present in water.

The ratio of total number of lone pairs in XeF_2 and XeF_4 are:

Calculate the number of lone pairs on central atom in the following molecule and predict the geometry. XeF_(4)