彩色电视画面的颜色是由______三种色光合成的.
用放大镜观察彩色电视画面,可以发现是由红、绿、蓝三种色光混合而成的,三种色光混合在一起的颜色是白色.
故答案为:红、绿、蓝.
新型的、民主平等的师生关系要求师生之间是[ ]
①师生人格平等,互相尊重
②师生互相学习,教学相长
③老师虽然是权威,与学生的身份、地位不同,但也是我们学习的合作者、引导者和参与者
④老师是我们的良师,也是我们的益友,但不是我们的朋友
A.①②③④
B.①②③
C.②③④
D.②③
A hat company ships its hats, individually wrapped, in 8-inch by 10-inch by 12-inch boxes. Each hat is valued at $7.50. If the company’s latest order required a truck with at least 288,000 cubic inches of storage space in which to ship the hats in their boxes, what was the minimum value of the order ?()
A. $960
B. $1,350
C. $1,725
D. $2,050
E. $2,250