If your question is whether or not your observation of the skin color and hair covering habits of an ostensibly Jewish stranger you see in a restaurant entitles you to question whether or not she is in fact Jewish, the answer is no.
If your question is whether or not your observation of the skin color and hair covering habits of an ostensibly Jewish stranger you see in a restaurant entitles you to question whether or not she is in fact Jewish, the answer is no.