\[
\boxed{
\begin{align_}
\text{a. i.} & \quad \bar{x} = 2.0 \\
\text{a. ii.} & \quad \sigma = 0.1 \\
\text{a. iii.} & \quad s_{\mathrm{x}} = 0.12 \\
\text{b.} & \quad X: \text{Weight of a single small bag of candies} \\
\text{c.} & \quad \bar{X}: \text{Mean weight of a sample of 16 small bags of candies}
\end{align_}
}
\]