I'm trying to hook up a new subwoofer using the wiring in my house that was installed when the house was built. The cable for the sub is just a coaxial cable with no ends, so I need to stick an RCA ...

The US uses two standard electrical plug types: Plug Type A and Plug Type B. Both have two parallel pins for power, while the latter has an additional grounding pin for safety. But if you look closely ...