A motherboard is one of the most essential parts of a computer system. It holds together many of the crucial components of a computer, including the central processing unit (CPU), memory and connectors for input and output devices. The base of a motherboard consists of a very firm sheet of non-conductive material, typically some sort of rigid plastic. Thin layers of copper or aluminum foil, referred to as traces, are printed onto this sheet. These traces are very narrow and form the circuits between the various components. In addition to circuits, a motherboard contains a number of sockets and slots to connect the other components.
 
        
                    
             
        
        
        
Answer:
Internet Control Message Protocol (ICMP) Echo Requests
Explanation:
A system that has Windows Firewall or antivirus or other third party antivirus enabled with their configuration setting set to default, ping command from another device will not be able to see if the device with an enabled firewall is alive.
The ping command sends Internet Control Message Protocol (ICMP) Echo Request to a destination device after the destination device will reply with a Reply packet. However, by default, firewalls, such as Windows firewall blocks ICMP Echo Requests from the external network and pinging will  work when the firewall is disabled or an exception is created that lets ICMP Echo Requests pass through the firewall.
 
        
             
        
        
        
Answer:2. electrical equipment shall be considered readily accessible to those to whom ready access is requisite when it is capable of being reached quickly for operation by using a portable ladder.
Explanation: