A:13
B:12
C:33
D:32
关于世界年降水分布特点的叙述,正确的是( )
When did the boy go to the zoo?
after , summer , comes , autumn ( . ) (连词成句)
____
已知实数x,y满足y≥1y≥2x-1x-y≥-2,则目标函数z=x+y的最大值为( )