Questions

The speed of the transmission data is generally determined by the cables or connectors we use for data transmission. In networking, layer-1 the physical is which deals with the network cables like pins, usb, connectors, etc... we use for data transmission.

Since, the starting statement carries a subject; R will be the first statement. The next statement describes why are they hunted, so Q follows P, as it states that what is being done with the horns. S would be the concluding statement and thus form a coherent paragraph.

The correct formation would be, ‘The Rhinoceros is hunted by poachers for its horn which is sold at high prices.’

The most common gas people breathe from clean air is nitrogen. Air is a mixture of gases, and the air on Earth contains about 78 percent nitrogen and about 21 percent oxygen. Argon, carbon dioxide neon, helium, methane, krypton, hydrogen and xenon are in much smaller amounts.