【简答题】(11分)化学与环境保护——探究酸雨的腐蚀性 我国道教发源地山东威海圣经山摩崖石刻,为国内罕见的大型道教石刻,可称为瑰宝。圣经山摩崖石刻的材质是大理石,主要成分是碳酸钙,现在字迹已模糊不清。摩崖石刻被腐蚀,是否是酸雨所致?试回答下列问题: (1)酸雨的成因:即使大气没有受到污染,正常的雨水或河水也呈微弱酸性(pH在5.6~7之间),原因是 。酸雨的酸性比正常雨水强,是因为雨水吸收了被污染的大气中的...
【简答题】土的液性指数0≤IL<1时,土处于 状态 。
【简答题】听对话选择正确答案(听两遍)。 1. Where was Jack yesterday? A. At school. B. At home. C. ln the park. D. ln the zoo. 2. What did Mary do last night? A. Watched a movie. B. Danced with Susan. C. Went to a concert. D....
【简答题】短文改错(共10小题;每小题1分,满分10分) Dear Tom, Last year I take a part-time job in the international camp for children. I have been telling one more worker will be needed this year and I think you are fit it. Why ...
【多选题】会务工作做得好坏,是影响会议质量和会议效果的重要因素。会务工作的特点有商业性、服务性、被动性、()。
【单选题】Part II Vocabulary & Structure (10 minutes) Directions; This part is to test your ability to construct correct and meaningful sentences. It consists of 2 sections. Section A Directions: In this secti...
A.
was; couldn't have taken
B.
hadn't been; couldn't take
C.
hadn't been; couldn't have taken
D.
have not been; couldn't have taken
【单选题】会务工作做得好坏,是影响会议质量和会议效果的重要因素。会务工作的特点不具有( )
【单选题】船载航行数据记录仪的电源系统包括 ( )