Final answer:
The pin number used for transmitting a positive signal on an RJ-45 straight-through patch cable is pin number 1.
Step-by-step explanation:
The pin number used for transmitting a positive signal on an RJ-45 straight-through patch cable is pin number 1. The connector on an RJ-45 patch cable has 8 pins, numbered from 1 to 8. Pin 1 is used for transmitting data in a straight-through cable. When a positive signal is sent over a straight-through cable, it means that the voltage on the wire is positive, indicating the presence of data.