贵金属基底冠喷砂常用材料是
A.40目的金刚砂
B.80目的金刚砂
C.40目的氧化铝砂
D.80目的氧化铝砂
E.40目的石英砂
参考答案:C
________ of the land in that district _______ covered with trees and grass.
A.Two fifth; is
B.Two fifth; are
C.Two fifths ; is
D.Two fifths; are
()Flash软件保存格式为。
A.ai
B.png
C.fla
D.pnd