Question: what type of bridge is the charles bridge
[{'answer': 'a bow bridge', 'provenance': [{'wikipedia_id': '515933', 'title': 'Charles Bridge', 'start_paragraph_id': 2, 'start_character': 109, 'end_paragraph_id': 2, 'end_character': 121, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Stone'}, {'answer': 'bow bridge', 'provenance': [{'wikipedia_id': '515933', 'title': 'Charles Bridge', 'start_paragraph_id': 2, 'start_character': 111, 'end_paragraph_id': 2, 'end_character': 121, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'a bow bridge with 16 arches'}, {'provenance': [{'wikipedia_id': '515933', 'title': 'Charles Bridge', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 497, 'bleu_score': 0.650072282262783, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11304718104227041674}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '515933', 'title': 'Charles Bridge', 'section': 'Section::::Abstract.', 'start_paragraph_id': 2, 'end_paragraph_id': 2, 'meta': {'evidence_span': ['it was built as a bow bridge with 16 arches shielded by ice guards', 'the Stone Bridge', 'he bridge is long and nearly wide, following the example of the Stone Bridge in Regensburg, it was built as a bow bridge']}}]}]