Consider the sets $A=\{xinR$:$x<mn\; id="EditorElement\_1025862">4</mn><mi\; id="EditorElement\_1025864">\}</mi>$ and

$B=\{xinR$: What is $B-A?$

$\{xinR$:$x>4\}$

$\{xinR$:$x>2\}$

$\{xinR$:$2>x4\}$

$0$