【单选题】有一辆车以速度10m/s的速度匀速行驶,车上有r人以速度1m/s向车后行走,则人相对地面的速度为()。
A. 11m/s
B. 10m/s
C. 9m/s
D. 1m/s
稳定的南风风速v1=3米每秒,某人向西快跑,速率v2=4米每秒。此人感受到的风速大小及风向分别为()
A. 25,西南风
B. 5,西南风
C. 25,东南风
D. 5,东南风
With ________, the seller identifies market segments, selects one or more, and develops products and services tailored to each selected segment.
A. Differentiation marketing
B. Target marketing
C. Product-variety marketing
D. Mass marketing
Which of the following is a psychographic segmentation variable?
Age
B. Social class
C. Income
D. Gender