Help the problem is 32 and 1-6 please

Ithink its b) built underground reservoirs

3. study 4.eat 5.play american football 6.write a card 7.practice piano 8.swim in the pool 9.paint a mural 10.listen to the band 11.dance at a party 12.drink milk 13.visit panama 14.open the card 15.prepare dinner 16.stay in the house 17.watch tv 18.write on the paper 19.study spanish 20.examine the paintings in the museum. i hope this : )