Answer:
A. data-link layer
Explanation:
Data-link layer is the first layer and allows a contiguous sequence of bits to be transmitted through the network.
On top of it is the Network Layer and it handles the task of routing network messages from one computer to another.
Then comes the Transport Layer which is the basic layer at which one network computer communicates with another network computer.
Answer:
Explanation:
The dual of a function means replace AND with OR and replace OR with AND.
XOR gate of A , B is
So, Dual of A XOR B is ( replace AND with OR and OR with AND)
Complement of A XOR B is 
(In finding compliment AND becomes OR and OR becomes AND ).
By inter changing the above product of terms
Complement of 
So, Dual of A XOR B = Complement of A XOR B.
Answer: Both Agile and waterfall model are software development models to deliver a final outcome in the form of a software product. Waterfall model is sequential process with the requirements beings rigid and defined before beginning the software development.
Agile method basically concerned with the requirements of the client. Here both testing and development is carried out at the same time.
Explanation:
More differences between the two include :
Waterfall model is easy to manage whereas in agile model as the the client requirements changes and wants more functionalities is becomes a bit more difficult to manage. the role of project manager is very crucial in waterfall model whereas the role of developers ans testers is more important in Agile model.
There are many answers to this question. The first step is normally a reboot, second, I would check witch task or service is taking up all the CPU cycles and check the system and error logs. The list goes on... I'm not sure how detailed you want to get.
