You've observed the following returns on SkyNet Data Corporation's stock over the past five years: $15$ percent, $-6$ percent, $18$ percent, $14$ percent, and $10$ percent.

a$.$ What was the arithmetic average return on the company's stock over this five$-$year period? $($Do not round intermediate calculations and enter your answer as a percent rounded to $1$ decimal place, e$.$g$.,32\mathrm{.}1.)$

b$-1.$ What was the variance of the company's returns over this period? $($Do not round intermediate calculations and round your answer to $5$ decimal places, e$.$g$.,\mathrm{.}16161.)$

b$-2.$ What was the standard deviation of the company's returns over this period? $($Do not round intermediate calculations and enter your answer as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

$\backslash$table$[[$a$.$ Average return,$10\mathrm{.}2],[$b$-1.$ Variance,$72\mathrm{.}16000],[$b$-2.$ Standard deviation,$8\mathrm{.}49]]$