[问答题] 简述网络财务的特点。

主观幸福感产生于活动本身而非活动目标的实现是（） ["判断理论","目标理论","活动理论"] You manage a software update infrastructure by using Windows Server Update Services (WSUS) 3.0. All client computers run Windows XP Professional Service Pack 3 (SP3). The client computers receive Automatic Updates from the WSUS server, and they are configured to install Automatic Updates immediately. From the Update Services console, you approve a required security update for all client computers. You need to force a client computer to apply the required security update as soon as possible. Which tool should you use? （） [" Secedit"," Wuauclt"," Wsusutil"," Gpupdate"] 简述变量分组的种类及应用条件。 在遥感数字图像处理中，为重点突出图像上的某些特征可采用（），为了突出图像的边缘、线状目标或某些亮度变化率大的部分，可采用（），为了改变图像像元的亮度值，可采用（）。 发电锅炉里管子常用的材料是（）。 ["20g或低合金钢管","20g或0Cr18Ni9Ti","20g或12Cr1MoVG","20g或流体管"] 简述网络财务的特点。