裸露在地表的玻璃钢管道要求在外表面树脂中加入（）等抗老化助剂。
参考答案：紫外线吸收剂
As a result of destroying the forest, a large ___ of desert ____ covered the land.[ ]
A. number; has
B. quantity; has
C. number, have
D. quantity; have
8×12-（-9）×11=______．
