A bag contains three different balls, one red (r), one blue(b), one white(w). TWO balls are drawn from the bag without replacement one after the other (at random without looking) and the colors recorded. This means once the first color is drawn, the first ball is kept out of the bag and only 2 colors remain when the second ball is drawn. List the sample space. [Use lower case letters for the colors, preserve the given order, commas separating pairs, no spaces.]