You$$ve observed the following returns on SkyNet Data Corporation$$s stock over the past five years: $16$ percent, $5$ percent, $19$ percent, $13$ percent, and $10$ percent.

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?