The bidding so far: (P)-1♣-X-?
Basic system: Standard American (or 2/1; I don't think it makes a difference. If it does, please address that system too).
Pertinent agreements: In an uncontested auction, 3♣ would be preemptive, 2♣ would be a limit raise or better, 4+ ♣, no 4 card major. 2NT balanced invite, 3NT balanced 13+ (not sure this is a good agreement, or why it's on the card, but there it is). After the double, 2NT is a preemptive raise in ♣, 3♣ is invitational ("Flip Flop"). Redouble would show 10+ points and imply no fit. Our agreement as to 2♣ now is unclear. Many people seem to think inverted raises should be off over a double. I'm not so sure, and this hand shows why. How do you bid now?

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