在空气中燃烧1.6克某化合物，生成4.4克CO2 和3.6克水，则该化合物是由 元素组成的，它的化学式为 。
碳，氧（C，H）；CH4
在表面粗糙度的评定参数中，微观不平度＋点高度符号是()。
A、Rg
B、Ra
C、Rx
D、Rz
Traditional IP packet forwarding analyzes the （1）IP address contained in the network layer header of each packet as the packet travels from its source to its final destination. A router analyzes the destination IP address independently at each hop in the network. Dynamic （2） protocols or static configuration builds the database needed to analyze the destination IP address (the routing table). The process of implementing traditional IP routing also is called hop-by-hop destination-based（3） routing. Although successful, and obviously widely deployed, certain restrictions, which have been realized for some time, exist for this method of packet forwarding that diminish its （4）. New techniques are therefore required to address and expand the functionality of an IP-based network infrastructure. This first chapter concentrate on identifying these restrictions and presents a new architecture, known as multipleprotocol （5）switching, that provides solutions to some of these restrictions.
（5）是（）
A.const
B.cast
C.mark
D.label
