【多选题】榨油厂要利用大豆期货进行买入套期保值的情形有( )。
【简答题】Nonverbal behavio r such as smile and laugh seem to cut across cultural lines. But in reality, they are often found to be not ________________.
【简答题】Why did the popularization of Welsh costume boost the Welsh woollen industry?
【简答题】How did Welsh keep their own language?
【简答题】How did the Welsh speakers fight hard to preserve Welsh?
【单选题】变压器原、副绕组中不能改变的物理量是( )。