Problem $12-9$ Calculating Returns and Variability $($LO$1)$

You've observed the following returns on Regina Computer's stock over the past five years: $11\%,-10\%,19\%,18\%,$ and $10\%.$

a$.$ What was the arithmetic average return on Regina's stock over this five$-$year perlod? $($Round the final answer to $1$ decimal place.$)$

Average return $\%$

b$-1.$ What was the varlance of Regina's returns over this period? $($Do not round Intermedlate calculations. Round the final answer to $5$ decimal places.$)$

Varlance $(3)$

b$-2.$ What was the standard deviation of Regina's returns over this perlod? $($Do not round Intermedlate calculations. Round the final answer to $1$ decimal place.$)$

Standard deviation $$