反映三视图投影特性的叙述正确的是()
A. 长对正、高平齐、宽相等
B. 真实性、积聚性、类似性
C. AB都正确
D. AB都不正确
已知圆锥的两个视图均为等腰三角形,则第三个视图是()。
A. 矩形
B. 圆
C. 梯形
D. 不规则图形
Since 1949, How many times of National Day military parades have been held?
A. 11
B. 12
C. 13
D. 15
What is the symbolic meaning of the color red of Chinese National Flag?
A. Hope
B. Fairness
C. Revolution
D. Bright