Questions

The logic in the given puzzle is 

Addition of numeric values of corresponding letters in the first three figures gives respective corresponding letter in fourth figure. 

i.e, A = 1 , W = 23 , B = 2 => 2 + 1 + 23 =26 = 'Z'

Similarly, L = 12, K = 11 , A = 1 => 1 + 11 + 12 = 24 = 'X'

Here the missing letter is 'X'.

Albatross

Australia is the smallest of all the continents

Here the given compound is MgSO4.

In the given compound, Sulphur (S) and Oxygen (O) are two non metals and Magnesium (Mg) is a metal.

In this compound, Sulphur and Oxygen reacts to form covalent bond and the metal Magnesium reacts with both non metals Sulphur and Oxygen to form ionic bonds.

Hence, in the given compound MgSO4 there are both covalent and ionic bonds.