Question: when did the usa place an embargo on cuba
[{'answer': 'March 14 , 1958', 'provenance': [{'wikipedia_id': '1105954', 'title': 'United States embargo against Cuba', 'start_paragraph_id': 9, 'start_character': 53, 'end_paragraph_id': 9, 'end_character': 68, 'bleu_score': 1.0, 'section': 'Section::::History.:Eisenhower era.\n'}]}, {'answer': 'October 19 , 1960', 'provenance': [{'wikipedia_id': '1105954', 'title': 'United States embargo against Cuba', 'start_paragraph_id': 1, 'start_character': 232, 'end_paragraph_id': 1, 'end_character': 250, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1105954', 'title': 'United States embargo against Cuba', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 997, 'bleu_score': 0.594031523886637, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8427124448550486605}, 'section': 'Section::::Abstract.'}]}]