离原点越远的等产量曲线代表的产量水平？
A 越低
B 越高
C 越不能达到
D 越不能确定

单项选择题在Photoshop中,不能用来绘制图标轮廓的是( )。 A. 仿制图章工具 B. 形状工具 C. 钢笔工具 D. 选框工具

单项选择题when Prof. Hoffmann was a teenager, he was walking into a department store on a trip to Florida, with my family for vacation, and seeing a public water fountain, which was marked “___________”.