This scentence translates to:
in the store you pay at _________.
the answer is la caja which means the cash register.
Hope this helps :-)
God Bless you!
Here in U.S we sing the Happy Birthday song but in Mexico they sing las mananitas when is some ones birthday , and because they don't really know any other song that they can sing in a birthday party and the song is really popular in birthday party .
Piensan.
Ten un día maravilloso