What Size?

One day, a blonde decided to build a brick wall, so she went to a home depot.
While a worker was walking down an aisle, he saw the blonde walking around in circles looking confused, so he went over and asked her what she wanted to make. She answered that she wanted to make a brick wall.
Then the worker asked her what size; after thinking thoroughly she answered, “And they say blondes are stupid; how am I supposed to know? There is no fence to measure.”