【名词&注释】
采样器(sampler)、强热带风暴(severe tropical storm)
[单选题]冰期相对水深0.0,0.2,0.4,0.6,0.8,1.0的测点流速分别为0.30m/s,0.42m/s,0.40m/s,0.31m/s,0.19m/s,0.06m/s,则该垂线平均流速为()m/s。
A. 0.31 B. 0.30 C. 0.29 D. 0.28