Question 225955
F' = Set of everything in U but NOT in F =  {Lower cost, Less time to see the sights, Can visit relatives along the way} 


D' = Set of everything in U but NOT in D = {Higher cost, More time to see the sights, Cannot visit relatives along the way, Less time to see the sights}

 
Now just look for the common elements in both sets. Since there are no common elements, this means that the result of the intersection between these sets is the empty set. 


See this <a href=http://www.algebra.com/algebra/homework/sets-and-operations/set-union-intersection.solver>solver</a> for more practice on set operations.