All Skelerena footage is DaiRanger footage.
The Bazooka is used to attack Skelerena.

All footage of the Power Cannon is new footage though. Here's a shot of the 6 Rangers with the Power Cannon.
Here's a shot of the Rangers inserting their Power Balls into the Cannon. First was Pink then Yellow then White then Red. There was no decent image of the Yellow Ranger putting her Yellow Ball into the Cannon.
Here's a shot of the Rangers inserting "Dai-Swords" into the Cannon.
Here's a shot of the flap on the Cannon and here's a shot of the Red and Blue Rangers psughing the flap in.
Here's a shot of the Rangers firing the Power Cannon.