题目

Complete the sentences with the given words in their proper forms(用括号中所给单词的适当形式完成下列句子，每空格限填一词):【1】The team are working on a couple of unsolved ________ of this century. (mystery)【2】Many important events were held in the ________ half of the year. (two)【3】The ________ is so exciting that you can have a lot of food for thought. (speak)【4】There’s a large ________ of soft drinks to choose from in this store. (various)【5】It’s a pity that the world famous church was ________ damaged by a fire. (serious)【6】The report sa体积为20cm3，质量为89g的铜球，计算说明此球是实心的还是空心的？若是空心的，在其空心部分装满水，求铜球的总质量为多少？（已知ρ铜＝8.9×103kg/m3）