Answer
{0,1,2,3,5,6,7,8,9}
Work Step by Step
The intersection of A and B (Denoted by A*upside down U*B) is the representation of all elements sets A and B share.
So, if the A set is {1,3,4,5,9}
and the B set is {2,4,6,7,8},
then the only element shared is {4}.
However, because there is a bar over the intersection of A and B, we will find the complement, or all numbers in the Universal set that are not included in the given set.
So, if the Universal set is {0,1,2,3,4,5,6,7,8,9}
then the complement is all numbers but {4}.
So the answer is {0,1,2,3,5,6,7,8,9}.