What are the rules for this?

What are the rules for this?. We are playing beer pong and my team has one cup left and the opposing team has three.  The opposing team hits our last cup and forces us to attempt at a rebuttal.  On the first shot of the rebuttal the ball hits the cups and ends up on top of all three c.
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We are playing beer pong and my team has one cup left and the opposing team has three. The opposing team hits our last cup and forces us to attempt at a rebuttal. On the first shot of the rebuttal the ball hits the cups and ends up on top of all three c