In the Venn diagram given below, 'circle' represents 'women'; 'Triangle' represents 'married', 'rectangle' represents 'under 30 years' and 'square' represents 'employed people'. The numbers given in the diagram indicate the number of persons in that particular category. How many unmarried women below the age of 30 are unemployed?
1
2
2
8
3
10
4
4