False, it is used in many places, not only in Spain.
Esta frase es utilizada en cartas informales = This phrase is used in informal letters
estimado señor = Dear Sir (Not correct)
Saludos cordiales = Best regards (Not correct)
De mi consideración = Of my consideration (Not correct)
Con cariño = Fondly (Correct I believe)
that means She is a classmate
Answer:
puedes ser mas especifico en tu pregunta? aunque sea agrega el cuento o algo para que podamos contestar.
Explanation: