Question: what is the inner core of the earth made from
[{'answer': 'some other elements', 'provenance': [{'wikipedia_id': '2939202', 'title': "Earth's inner core", 'start_paragraph_id': 2, 'start_character': 289, 'end_paragraph_id': 2, 'end_character': 308, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'iron -- nickel alloy'}, {'answer': 'an iron -- nickel alloy and some other elements'}, {'answer': 'an iron -- nickel alloy'}, {'provenance': [{'wikipedia_id': '2939202', 'title': "Earth's inner core", 'section': 'Section::::Abstract.', 'start_paragraph_id': 2, 'end_paragraph_id': 2, 'meta': {'evidence_span': ["There are no samples of the Earth's core available for direct measurement, as there are for the Earth's mantle. The information that we have about it mostly comes from analysis of seismic waves and the magnetic field. The inner core is believed to be composed of an ironnickel alloy with some other elements. The temperature at the inner core's surface is estimated to be approximately or 9806\xa0°F, which is about the temperature at the surface of the Sun.\rhighlight sentence(s) containing evidence, not only the answer", 'The inner core is believed to be composed of an ironnickel alloy with some other elements.', "There are no samples of the Earth's core available for direct measurement, as there are for the Earth's mantle. The information that we have about it mostly comes from analysis of seismic waves and the magnetic field. The inner core is believed to be composed of an ironnickel alloy with some other elements. The temperature at the inner core's surface is estimated to be approximately or 9806\xa0°F, which is about the temperature at the surface of the Sun."]}}]}]