Hi,

can anybody explain me how to construct an algebra and $\displaystyle \sigma$-algebra generated by $\displaystyle K$, if $\displaystyle K=\{\{x\}\mid x\in X\}$ and $\displaystyle X$ - universal set.

I guess it also depends on the fact whether $\displaystyle X$ is finite or infinite, countable or uncountable, does it?