\( \newcommand{\cat}[1] {\mathrm{#1}} \newcommand{\catobj}[1] {\operatorname{Obj}(\mathrm{#1})} \newcommand{\cathom}[1] {\operatorname{Hom}_{\cat{#1}}} \newcommand{\multiBetaReduction}[0] {\twoheadrightarrow_{\beta}} \newcommand{\betaReduction}[0] {\rightarrow_{\beta}} \newcommand{\betaEq}[0] {=_{\beta}} \newcommand{\string}[1] {\texttt{"}\mathtt{#1}\texttt{"}} \newcommand{\symbolq}[1] {\texttt{`}\mathtt{#1}\texttt{'}} \)

Lebesgue measurable sets.

The following sets meet the criteria to be Lebesgue measurable:

1. Every [...] set is Lebesgue measurable.
2. A countable [...] of Lebesgue measurable sets is Lebesgue measurable.
3. Every [...] set is Lebesgue measurable.
4. The [c________] of a Lebesgue measurable set \( E \) is Lebesgue measurable.
5. A countable [...] of Lebesgue measurable sets is Lebesgue measurable.

Two others are:

• Every set of Lebesgue outer measure [...] is measurable. These sets are called [...] sets.
• The empty set \( \emptyset \) is Lebesgue measurable.

The proofs are on the reverse side, along with a repeat of the definition of Lebesgue measurability.