A:
Theoretically , yes you can, depending on how old the receiver is and what it's wattage is. Look at the kind of speaker jacks on the back of the receiver. If the jacks are the kind you connect a wire directly to, the wattage is probably too high. However, if there are RCA jacks you can probably get an adapter for the 3.5mm plug and connect it to the RCA jacks. Also, there might be an AUX OUT jack, and of there is, it would be better to use that.
Just beware that these kinds of speakers aren't meant to handle high wattage.