I work for an electronics chain as a sales assistant. Everyone has to work one weekend day, as that's when our store is busiest. I had been working a Sunday through Thursday shift, but my manager just told me that I'll be switching to a Tuesday through Saturday shift next month. The problem is that Saturday is my Sabbath day. My religious beliefs require me to refrain from working and other worldly pursuits on that day. One of my coworkers is willing to switch shifts with me, but our manager won't allow it. She said that everyone would want to change their schedules, and it would be too much of a hassle. Do I have any rights here?