90#汽油的抗爆性()70#汽油。
A.高于
B.低于
C.等于
D.不一定
参考答案:A
This book is specially intended _____ those who want to improve their writing. [ ]
A. by
B. at
C. with
D. for
具有实用价值和美感作用的包装外观形体,是指包装审美的()
A.结构美
B.造型美
C.装饰美
D.材料美