建筑物的经济寿命是指建筑物从建成之日起预期产生的收入等于其运营费用时的持续年数。 ( )
参考答案：错
根据句意和首字母提示补全单词.
1. Don't w________ water. Please turn off the cock after you wash your hands.
2. Gold, silver and iron are all m_______.
3. It's more and more important for everyone to save e_______ now.
4. Air p_______ is quite harmful to our health.
5.The students from a green school are helping collect waste paper and bottles for r________.
拉西法、一氧化氮还原法、HPO法三种工艺中耗氨最少的工艺是HPO法。
词.