Questions

In the adult heart, blood in the right chambers of the heart cannot enter the left chambers without passing through the lungs is correct regarding mammalian heart.

From the aboe given options, only extreme and unexplained tiredness is the symptom of AIDS.

The other symptoms of AIDS include: recurring fever, thrush — a thick, whitish coating of the tongue or mouth that's caused by a yeast infection and sometimes accompanied by a sore throat, diarrhea that lasts more than a week, headaches, lightheadedness, and/or dizziness.

Hubs are specified or operate at Layer1 i.e, the physical layer in the OSI model. Hubs regenerate electrical signals. A hub sends data packets (frames) to all devices on a network, regardless of any MAC addresses contained in the data packet.

Lothal

It is using a router to answer ARP requests. This will be done when the originating host believes that a destination is local, when in fact is lies beyond router.