A teacher notices that the morning of an exam, many of the students seem tired. He decides to ask all 30 students how many hours they slept the night before. 2 slept 7 hours, 3 slept 6 hours, 6 slept 5 hours, 7 slept 4 hours, 8 slept 3 hours, 2 slept 2 hours, 1 slept for 1 hour, and 1 did not sleep at all. The random variable that we are interested in is the number of sleeping hours. This information can be summarized IN the following table.

X (sleeping hours)	7	6	5	4	3	2	1	0
# of students	2	3	6	7	8	2	1	1

Use your answer in the previous part to calculate the standard deviation of the random variable, rounded to 1 decimal place.