Mr Green,Jenny has come to see you.She________for you in your office now.
A:will wait
B:waits
C:is waiting
D:has waited
顺序写出还原氧化铜的三个反应的化学方程式:甲:____ ,乙:____ ,丙:____ .上述反应中,不属于置换反应的是____ (写编号)
世界着名的“低地国”是 ( )