Surface areas on walls, under loose woodwork, between bricks and around other bat entryways often have a smooth, polished appearance. The stained area is slightly sticky, may contain a few bat hairs, and is yellowbrown to blackish brown in color.
cross connections What is a Cross Connection? A cross connection is a point in a plumbing system where the potable water supply is con-nected to a non-potable source. Briefly, a cross connection exists whenever the drinking water system is or could be connected to any non-potable source (plumbing fixture, equipment used in any plumbing system).
When I studied for the CCNA, I learned which devices should be connected using a straight through cable and which using a crossover cable. For example take this explanation for question one from a study site. Group 1: Router, Host(PC), Server. Group 2: Hub, Switch.