I'm building an experiment in which I have a pool of 22 questions and answers (each question and answer is a block by itself). There are 2 conditions which will both be presented to participants in a random order. Each condition should include 11 randomly selected questions (in the form of blocks) so that no question is repeated more than once. I wish to randomly and evenly present all of the 22 questions so some random 11 questions would appear in the first block, and the other 11 questions would appear in the second block. I would really appreciate some help as I haven't yet found a solution to this issue :)