You don't. The city will return back to normal once you obtain the badge at Snowpoint city.
No. Just like in Pokemon Pearl with the Pal Park you can only trade from Pokemon pearl to black, not back
No, but you can send Pokemon from Pokemon Pearl to Pokemon Black. In-depth details: Remember that if you trade from Pokemon Pearl to Pokemon Black, you must have the Japanese version of Pearl since it's quite region locked.
Yes you can.
you can't trade Pokemon, but you can transfer pearl Pokemon to gen v (your Pokemon black) using the Pokemon transfer available after you beat the main storyline. it is on the route next to black city. hope i helped!
No
you have to transfer from diamond, pearl, or platinum or trade with a friend
Dawn never was on pokemon black and white she was only on pokemon diamond and pearl.
yes.though of course you cannot trade or battle with Pokemon from the Unova Region as they are new, and Pokemon Pearl will not recognize them.
We dont answer questions like this
You have to Beat Prof.Oak and Beat him with a Pokemon with "Rough Pearl" Attached to it.
yes
in pokemon pearl,diamond or platinum you have to eight badges in pokemon black and then trade kadabra to you from yourself and it will evolve