The answer to the given question is (B) PAN.
A PAN (personal area network) connection is <u>a network used for interconnecting devices centered on a person’s workspace</u>. Bluetooth is a type of wireless PAN. Bluetooth-based wireless PAN connection is also called a <em>piconet</em>. Other examples of PAN that is not wireless based include a USB drive.
Email client as port 25 is the default port for an email server.
Answer:
28 years
Explanation:
Let's represent present age of Chris and Dom as C and D respectively. Then since ratio of present age of Chris and Dom is 3:4. Therefore,
...(1)
Now, it is given that in 7 years their age ratio will become 4:5. Therefore,


Using value of C from equation(1),


Thus, present age of Dom is 28 years.
Answer:
B. blocking I/O
Explanation:
Most of the input and output request placed to the computer considers the blocking request. It means that the controls given cannot be returned to the given application until and unless the input/output is complete.
Thus, blocking the input/output does not return till the input and output is complete.
With a blocking I/O, the process is moved to a wait queue when the I/O request is made, and it moved backs to the ready queue as soon as the request is complete, thereby allowing the other processes to run in the meantime.
Thus (B) blocking I/O is the answer.