In the terms of Economics:
b.What you expect would happen to (a) if women's salary were to increase so that women make 10% more than men, for the same job.
c.Whether providing a subsidy for day care usage (returning 30% of the day care cost as tax benefits) is likely to affect (a), and for whom (compare different 'types' of women based on earning potential, skills, number of children, etc.)