One hundred teachers attended a seminar on mathematical problem solving. The attitudes of a representative sample of 12 of the teachers were measured before and after the seminar. The differences between their preseminar scores and post-seminar scores are shown below.
\begin{tabular}{|l|l|l|l|l|l|l|l|l|l|l|l|}
\hline 4 & 7 & 6 & -3 & 2 & 2 & -3 & 3 & -2 & -2 & 1 & 4 \\
\hline
\end{tabular}
(a) What is the range of the scores?
(b) What is the standard deviation of the scores? Round your answer to the nearest tenth, if necessary.
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Step 1 ：Given the scores are [ 4, 7, 6, -3, 2, 2, -3, 3, -2, -2, 1, 4].

Step 2 ：To find the range, we need to identify the highest and lowest values in the given data set and subtract the lowest value from the highest value.

Step 3 ：The highest score is 7 and the lowest score is -3.

Step 4 ：So, the range of the scores is \(7 - (-3) = 10\).

Step 5 ：To find the standard deviation, we first find the mean (average) of the data set, then subtract the mean from each data point and square the result to get the squared differences.

Step 6 ：The variance is the average of these squared differences.

Step 7 ：The standard deviation is the square root of the variance.

Step 8 ：After calculating, we find that the standard deviation of the scores is approximately 3.3.

Step 9 ：This indicates that the scores are spread out around the mean by about 3.3 units on average.

Step 10 ：Final Answer: (a) The range of the scores is \(\boxed{10}\). (b) The standard deviation of the scores is \(\boxed{3.3}\).