Question: where does the brazos river start and stop
[{'answer': 'Llano Estacado', 'provenance': [{'wikipedia_id': '224722', 'title': 'Brazos River', 'start_paragraph_id': 4, 'start_character': 158, 'end_paragraph_id': 4, 'end_character': 172, 'bleu_score': 1.0, 'section': 'Section::::Geography.\n'}]}, {'answer': 'Gulf of Mexico', 'provenance': [{'wikipedia_id': '224722', 'title': 'Brazos River', 'start_paragraph_id': 1, 'start_character': 289, 'end_paragraph_id': 1, 'end_character': 303, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '224722', 'title': 'Brazos River', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 438, 'bleu_score': 0.684528608751599, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10255641288519001682}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '224722', 'title': 'Brazos River', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ['The Brazos River ( ), called the "Río de los Brazos de Dios" (translated as "The River of the Arms of God") by early Spanish explorers, is the 11th-longest river in the United States at from its headwater source at the head of Blackwater Draw, Curry County, New Mexico to its mouth at the Gulf of Mexico with a drainage basin.', 'The Brazos River ( ), called the "Río de los Brazos de Dios" (translated as "The River of the Arms of God") by early Spanish explorers, is the 11th-longest river in the United States at from its headwater source at the head of Blackwater Draw, Curry County, New Mexico to its mouth at the Gulf of Mexico with a drainage basin. Being one of Texas\' largest rivers, it is sometimes used to mark the boundary between East Texas and West Texas.', 'The Brazos River ( ), called the "Río de los Brazos de Dios" (translated as "The River of the Arms of God") by early Spanish explorers, is the 11th-longest river in the United States at from its headwater source at the head of Blackwater Draw, Curry County, New Mexico to its mouth at the Gulf of Mexico with a drainage basin.']}}]}, {'provenance': [{'wikipedia_id': '180969', 'title': 'Colorado River (Texas)', 'section': 'Section::::History.\n', 'start_paragraph_id': 6, 'end_paragraph_id': 6, 'meta': {'evidence_span': ['Briarcliff. After passing through Austin, the Colorado River continues flowing southeast until emptying into Matagorda Bay on the Gulf of Mexico, near Matagorda. The Colorado River, which means "red" or "reddish" river in Spanish, was frequently confused by Spanish explorers with the Brazos River to the north. The European discoverer of these two neighboring rivers called the present Colorado River the Brazos de Dios, and called the present Brazos the Colorado River, and later the names were reversed. The upper Colorado River was controlled by Comanches', 'Briarcliff. After passing through Austin, the Colorado River continues flowing southeast until emptying into Matagorda Bay on the Gulf of Mexico, near Matagorda. The Colorado River, which means "red" or "reddish" river in Spanish, was frequently confused by Spanish explorers with the Brazos River to the north']}}]}, {'provenance': [{'wikipedia_id': '37289186', 'title': 'Salt Fork Brazos River', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ['The Salt Fork Brazos River is a braided, highly intermittent stream about long, heading along the edge of the Llano Estacado about east-southeast of Lubbock, Texas. From its source, it flows generally east-southeastward to join the Double Mountain Fork to form the Brazos River about west-northwest of Haskell, Texas. The Salt Fork stretches across portions of Crosby, Garza, Kent, and Stonewall counties of West Texas. The Salt Fork Brazos River begins as a dry channel (draw) near the edge of the', 'The Salt Fork Brazos River is a braided, highly intermittent stream about long, heading along the edge of the Llano Estacado about east-southeast of Lubbock, Texas.']}}]}]