Question

Use the given diagram to find number of elements in $B-(A-C)$

Answer 1

$A-C$ has the elements which are written in circle for $A$, but outside the circle for $C$.
So, $A-C=$ { $a,b,c,d,g$ }
$B-(A-C)$ has the elements which are written in the circle for $B$ except for the elements { $a,b,c,d,g$ }.
So, $B-(A-C)=$ { $e,f,h,j$ }