i is insuff:
ii is also insuff: it could be dec. or jan.
i and ii togather suff because she must be hired in 2nd week of a given month. if we calculate 100 days in reverse order from the last of day of april, her hiring day falls somewhere in 3rd week of january. if we do the same thing again from 1st day of april, her hiring day falls somewhere in 3rd week of december. but this is not possible because she was hired on 2nd week of the month. however it is also not possible to have the hiring day on 3rd week of january because the information given says that she was hired on 2nd week but it doesnot make any effect.
so she was hired on 2nd week of jan...