If three devices are plugged into one port on a switch and two devices are plugged into a different port, how many collision domains are on the switch?

Collision domain is a portion in the network where there is a possibility of formation of packets. This occurs when two or more devices are able to send a packet to a single switch or port on the network that is shared, on the same time. It was noted that this collision domain reduces the efficiency of the network. 

For this item, the first packet is the whole switch with the three devices. Next one would be first of the three devices that is connected to the other port. Similarly, the third one would be the second of the three devices that is also connected to the switch. Therefore, the answer is 3. 

Cin carbonh in hydrogeno in oxygen