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In order to pool questions together, click on question in an assignment you'd like to create a pool with. Scroll to the bottom and click the green + next to 'Question Pooling' to add a question. (notice: right now pooling can only be done on the older code base, featured below. We're working to bring it to the newer interface.)
Click Add, and search for questions (or enter in a question id) you'd like to pool, add questions as you normally would.
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