A vessel would be referred to as tender when the weight of the cargo is().
A. evenly distributed vertically and the double bottoms are full
B. concentrated low and the double bottoms are empty
C. concentrated low and the double bottoms are full
D. concentrated high and the double bottoms are empty
查看答案
采用热风再循环或暖风器可有效降低低温腐蚀。
A. 正确
B. 错误
同一基因型不因环境条件改变而产生不同表型。
A. 正确
B. 错误
按照随机原则抽取样本,并对总体的特征做出推断的调查方式是()
A. 抽样调查
B. 普查
C. 统计报表调查