If a person's income increases from Rs 20 lakhs per year to Rs 24 lakhs per year and tax increases from Rs 3,50,000 to Rs 4,00,000 the marginal tax rate is
A hand made paper workshop can hire 8 craftsmen by paying them Rs 400 per person per day. The 9th craftsman demands Rs 450 per day. If this craftsman is hired then all other craftsmen must be paid Rs 450. The marginal resource (labour) cost of the 9th craftsman is