1. A production facility employs 20 workers on the day shift, 10 workers on the swing shift, and 5 workers on the graveyard shift. A quality control consultant is to select 4 of these workers for in-depth interviews. Suppose the selection is made in such a way that any particular group of 4 workers has the same chance of being selected as does any other group. What is the probability that at least two different shifts will be represented among the selected workers? Round your answer to three decimal places