Pls help will give brainless

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

While scuba diving, rajeev dove to a depth of 12.6 feet below the surface of the water and then descended another 8.7 feet. what expression can be used to find rajeev's new position? 12.6 – 8.7 –12.6 – 8.7 –12.6 – (–8.7) 12.6 – (–8.7)

Select the correct answer from each drop-down menu. the table shows the annual sales revenue for different types of automobiles from three automobile manufacturers. sales revenue (millions of dollars) suv sedan truck marginal total b & b motors 22 15 9 46 pluto cars 25 27 10 62 panther motors 26 34 12 72 marginal total 73 76 31 180 the company with the highest percentage of sales revenue from sedans is . of the annual sales revenue from suvs, the relative frequency of pluto cars is .