Consider the following returns for two investments, A and B$,$ over the past four years:

Investment $1$: $2\%8\%4\%6\%$

Investment $2$: $6\%12\%8\%10\%$

a$-1.$ Calculate the mean for each investment. $($Round your answers to $2$ decimal places.$)$

a$-2.$ Which investment provides the higher return?

b$-1.$ Calculate the standard deviation for each investment. $($Round your answers to $2$ decimal places.$)$

b$-2.$ Which investment provides less risk?

c$-1.$ Given a risk$-$free rate of $1\mathrm{.}2\%,$ calculate the Sharpe ratio for each investment. $($Round your answers to $2$ decimal places.$)$