One hundred teachers attended a seminar on mathematical problem solving. The attitudes of representative sample of 12 of the teachers were measured before and after the seminar. A positive number for change in attitude indicates that a teacher's attitude toward math became more positive. The twelve change scores are as follows.
3; 9; −1; 2; 0; 4; −2; 1; −1; 5; 4; −3

What is the standard deviation for this sample? (Round your answer to two decimal places.)


What is the median change score? (Round your answer to one decimal place.)