Answer
$U$
Work Step by Step
The symbol $\cap$ represents the intersection of two sets (for example $A$ and $B $), which is a set made up of all elements belonging to both sets $A$ and $B$.
The symbol $\cup$ represents the union of two sets (for example $A$ and $B$ ), which is a set made up of all elements belonging to set $A$ or set $B$.
The complement ($A'$) of a set ($A$) is the set of all elements in the universal set that don't belong to set $A$.
We start by finding $\emptyset'$
The complement of the empty set is the universal set.
$\emptyset' = U$
$\therefore (U \cap \emptyset') \cup R = (U \cap U) \cup R $
$(U \cap U) = U$
$(U \cap U) \cup R = U \cup R = U$
