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
D and E are points on side AB and AC of ΔABC. DE is parallel to BC. If AD:DB = 2:5 and area of ΔADE is 8 sq cm, what is the ratio of area of ΔADE: area of quadrilateral BDEC?