Skewers for Dinner Again!

Hello Chesskid kids!  Have you ever had a skewer or shish kabob?  We've done this tactic before, so click here if you need to review. This delicious tactic looks very similar to a pin, but the more valuable piece is in front.

I'll do the first puzzle for you.  Start noticing when pieces are lined up along ranks, files, or diagonals!

 
White won a rook for a bishop and a pawn.  Rooks are 5 dollars and bishops are 3 so that's a good deal for white!
Now you try!  This time it's black to move.  Do you see how white's queen and rook are lined up along the diagonal again?  How could black's fianchettoed bishop make a skewer?

 
Super!  Black to move again...
 
 
Excellent.  And how do you think this position arose?  It's from a World Championship match between Petrosian and Spassky!!  See if you can figure out how Spassky made this trick happen in two moves.
 
 
You must be World Championship material!
Now for a super duper hard one.
 
White to move.  Can you get a skewer on the back rank in two moves?  (See who's lined up?)
 
Fantastic skewering, chess friends!  See you next week!