题目

For our future generations, we must show respect for those _______job is to protect nature heart and soul. A. who                  B. which                C. that                    D. whose 答案：B4．用化学用语填空（1）地壳中含量最多的元素是O．（2）两个氮分子2N2．（3）碳酸钠溶液中大量存在的阴离子CO32-．