The stock of CM Punk, Inc. has earned annual returns of $5\%,-2\%,8\%,12\%,$ and $4\%$ over the last five years, respectively. What is the arithmetic average and standard deviation of these returns?

Multiple Choice

Arithmetic average $=5\mathrm{.}40\%$; Standard deviation $=4\mathrm{.}63\%$

Arithmetic average $=5\mathrm{.}40\%$; Standard deviation $=5\mathrm{.}18\%$

Arithmetic average $=6\mathrm{.}75\%$; Standard deviation $=29\mathrm{.}45\%$