Should he give the telephone worker a tip even though he has a salary?

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Is it permissible for her to accept gifts from the mothers of children whom she teaches in their homes?
Ruling on giving tips to plumbers, carpenters and phone company employees

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Is it permissible for her to accept gifts from the mothers of children whom she teaches in their homes?
Ruling on giving tips to plumbers, carpenters and phone company employees

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