Final answer:
A T3 line uses two pairs of copper wires, can handle 672 simultaneous conversations, and has a transmission rate of 44.736 Mbps. The mean speed testing hypothesis would include a null hypothesis of equal to 3 Mbps and an alternative that it's greater than 3 Mbps. The high-voltage wire claim is false as they are not insulated but held aloft by insulators.
Step-by-step explanation:
The question is pertaining to T3 lines, which are a type of telecommunications circuit. A T3 line uses two pairs of copper wires to carry up to 672 simultaneous conversations and has a transmission rate of 44.736 Mbps.
Regarding your hypothesis testing question for the mean speed of a cable internet connection, the null hypothesis (H0) would state that the mean speed is three megabits per second (≤3 Mbps). The alternative hypothesis (Ha) would be that the mean speed is more than three megabits per second (>3 Mbps).
As for the statement about high-voltage wires, it is false. The high-voltage wires are indeed held aloft by insulating connectors, but these wires are not wrapped in insulating material; they are bare due to the high voltage and are insulated by the air surrounding them.