At one hospital there is some concern about the high turnover of nurses. A survey was done to determine how long (in months) nurses had been in their current positions. The responses (in months) of 20 nurses were as follows. 31 10 13 22 33 44 35 50 20 16 15 31 37 34 36 19 28 39 16 44 Find the interquartile range. (Enter an exact number.) IQR =