1.The scientists from___USA live in___Ninth Street

1.The scientists from___USA live in___Ninth Street
A./,the B.the,/
我选的A答案是B,不是序数词前用the吗?
2.The market isn't far from here.It's only___ bicycle ride.
A.half an hours' B.half an hour's
我选的A答案是B,为什么?
3.The boy always stays there for___.
A.one and half hour B.one and a half hour C.one and half hours
D.one and a half hours 为什么选D?
4.Twelve___were hurt,but no ___were lost in that accident.
A.person,life B.people,lives C.peoples,lives D.persons,life
people不是不可数吗?
5.These Germans want to have some___for supper,so they decided to catch___now.
A.fish,many B.fishes,much C.fish,much D.fishes,many
fish不是不可数吗?