已知：6.4克铜与适量的浓硝酸反应，当铜完全溶解后，共收集到NO和NO2混合气体共2.24升（已折算为标准状况）．求：
Don't be . You can't make such great progress in a day. It takes time.
He is organized and is often . I hope he will have more at his business.
我国降水空间分布特点是（ ）
