"Blond buying a new tv." joke

A blonde walked into an electrical store and said to the man behaind the counter...
"i would like to buy that tv please."
the man behind the counter said,
"no because you are blonde."
the blond walked out and went home and dyed her hair red. She went back to the store and said to the man behind the counter,
"i would like to buy that tv please."
the man behind the counter said,
"no because you blonde."
she went home and dyed her hair black and went back into the store and said to the man behind the counter,
"i would like to buy that tv please."
the man behind the counter said,
"no because your a blonde."
the blonde said to the man,
"how do you know im blonde when my hair is dyed?"
the man behind the counter replied,
"it is not a tv it is a microwave!"