【简答题】material flow ________
【单选题】进行物质流动分析需要关注以下哪项( )Which of the following should be taken into attention in conducting a material flow analysis( )
A.
系统组分 The components of a system
B.
物质库存及存量 Material in-use stock and its size
C.
系统各组分间物质流动关系(流动强度和方向) The material flow relationship among system components (flow rate and direction)
【简答题】由数字1,2,3,4组成五位数 . a 1 a 2 a 3 a 4 a 5 ,从中任取一个记ξ为组成这个数的相同数字的个数的最大值,则ξ的数学期望为______.
【单选题】开展物质人为流动分析时应优先选择( )When carrying out a material anthropogenic flow analysis, priority should be given to ( )
A.
物质流动不受人类活动影响的物质 The material whose flow cannot be affected by human activity
B.
物质流动受人类活动影响较小的物质 The material whose flow is lightly affected by human activity
C.
物质流动受人类活动影响较大的物质 The material whose flow is strongly affected by human activity
D.
物质流动受人类活动与自然因素影响程度相当的物质 The material whose flow is affected by human activities to the same extent as natural forces
【单选题】OSPF 发送协议报文使用 的 组播地址是
【单选题】下列各项中,属于企业外来原始凭证的是( )。(2019)
【简答题】随机函数的应用: 1) 从1到10中随机选取10个整数,构成一个长度为10的数组a2,并输出a2 2) 创建一个数值服从均值为10、方差为0.6的正态分布组成的3行3列随机数组a3,并输出a3 3) 创建一个[0,1]区间的2行4列随机数组a4,并输出a4 4) 把3)中的数组a4的类型转换为字符串,然后再输出a4