 <translate> The volume of the slab is 100 * 100 * .5 = 5000 cubic feet. So it weighs 5000 * 150 = 750000 pounds. That means the cost is 750000 * $0.02 = $15,000 per house. So the total cost for all 3 houses is $15000 * 3 = $45,000.
Thus, the answer is 45000. <yor> Àpapọ̀ òrùlé náà jẹ́ 100 * 100 *.5 = 5000 ẹsẹ̀ kóbù. Nítorí náà, ó wúwo 5000 * 150 = 750000 poun. Ìyẹn túmọ̀ sí pé iye owó ilé kan jẹ́ 750000 * $0.02 = $15,000. Nítorí náà, iye tí ilé mẹ́ta náà ná jẹ́ $15000 * 3 = $45,000. Nítorí náà, ìdáhùn rẹ̀ jẹ́ 45000. 