This would mean "What is the date tomorrow?"
Cual es la - What is the feche de - date manana - tomorrow
(Sorry, my computer doesn't support accent marks)
To reply, say "The date tomorrow is [DATE]" For example, to say The date tomorrow is April 1st, it is:
La fecha de mañana es uno (1) de abril.
(Remember in Spanish, they don't capitalize months.)
The question "¿Cuál es la fecha de mañana?" means "What is the date tomorrow?" To answer, you provide the date in Spanish, such as "La fecha de mañana es uno (1) de abril" for April 1st.
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