The Earth's core has been taken as a fact.
Are you completely agree about this?
The Earth has a core?
How people can prove this if nobody has seen it?
This is something you can look up - quite easily - online.
Tengo entendido que el campo magnetico de la tierra es un indicio de la existencia del núcleo terrestre.
Do you see the air? Then stop breathing and you will recognise its existence without seeing it, quickly. But as a matter of fact, using sensors, and sensing earthquakes, it is possible to be sure that earth has a core as what this core is made of.
And if you was thinking about "Hollow Earth hypothesis"... there are some contrary evidences for that:
Andreaa -> Puedes hacer un resumen breve de lo que postula Giuliana, porfavor :-)
Estoy escuchando un video de youtube de ella, pero entiendo solamente la mitad de la mitad de la mitad ahahah