下列说法正确的是（） ["高雷诺数下容易转捩是因为惯性力大，扰动大","马赫数是惯性力与粘性力之比","层流和紊流的判断依据的是上临界雷诺数","雷诺输运方程和随体导数是完全等价的"]
在原子里质子数等于（）。 ["中子数","电子数","中子数和电子数之和","原子量"]
What are three considerations when choosing the QoS model to deploy in a network？ （） [" the routing protocols being utilized in the network"," the applications utilizing the network"," the traffic destinations"," network addressing scheme"," cost of implementation"," the amount of the control needed of the resource"]
井田制
按目标利润预测的目标成本应当等于（）。
试举例论述艺术符号的特性。
