What is the anwser for 1 (1/11-7d/17)

This is geometry. could anyone ? i can't fail this class. my grade is quite low already.

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Apolice office claims that the proportion of people wearing seat belts is less than 65%. to test this claim, a random sample of 200 drivers is taken and its determined that 126 people are wearing seat belts. the following is the setup for this hypothesis test: h0: p=0.65 ha: p< 0.65 find the p-value for this hypothesis test for a proportion and round your answer to 3 decimal places.