Mo Yan is good at writing. By now, he has w____ many novels.
17-8=____
9+3=____
一个水池有两个进水管,单独开甲管注满水池需2小时,单独开乙管注满水池需3小时,两个同时开注满水池的时间是____ 小时.
我国跨经度最广的省区是( )
下面各组数是三角形的三边的长,则能构成直角三角形的是( )