Final answer:
Lemons are not served with tap water upon request only. It depends on the establishment's policies.
Step-by-step explanation:
No, lemons are not served with tap water upon request only. Whether or not lemons are served with tap water depends on the establishment and its policies. Some restaurants may automatically serve lemons with tap water, while others may provide lemons only upon request. It is important to note that these practices can vary from place to place.