Question: What is the highest point of the state where Bluffton Airport is located?

full_context: Document 1: Oklahoma: Oklahoma has four primary mountain ranges: the Ouachita Mountains, the Arbuckle Mountains, the Wichita Mountains, and the Ozark Mountains. Contained within the U.S. Interior Highlands region, the Ozark and Ouachita Mountains mark the only major mountainous region between the Rocky Mountains and the Appalachians. A portion of the Flint Hills stretches into north-central Oklahoma, and near the state's eastern border, Cavanal Hill is regarded by the Oklahoma Tourism & Recreation Department as the world's tallest hill; at 1,999 feet (609 m), it fails their definition of a mountain by one foot.
Document 2: Bluffton, Texas: Bluffton is an unincorporated community in Llano County, Texas, United States. According to the Handbook of Texas, the community had an estimated population of 75 in 2000. The population report in 2011 was 269.
Document 3: Campbell Hill (Ohio): Campbell Hill is, at 1,550 feet (470 m), the highest point in elevation in the U.S. state of Ohio. Campbell Hill is located within the city of Bellefontaine, 2 miles (3.2 km) northeast of downtown.
Document 4: Palm Beach County Glades Airport: Palm Beach County Glades Airport , also known as Pahokee Airport, is a county-owned, public-use airport in Palm Beach County, Florida, United States. It is located three nautical miles (6 km) southwest of the central business district of Pahokee, Florida. The airport is owned by Palm Beach County and operated by the Palm Beach County Airports Department. It is included in the National Plan of Integrated Airport Systems for 2011–2015, which categorized it as a "general aviation" facility.
Document 5: Portland, Oregon: Though much of downtown Portland is relatively flat, the foothills of the Tualatin Mountains, more commonly referred to locally as the ``West Hills '', pierce through the northwest and southwest reaches of the city. Council Crest Park, commonly thought of as the highest point within city limits, is in the West Hills and rises to an elevation of 1,073 feet (327 m) The city's actual high point is a little - known and infrequently accessed point (1,180 feet) near Forest Park. The highest point east of the river is Mt. Tabor, an extinct volcanic cinder cone, which rises to 636 feet (194 m). Nearby Powell Butte and Rocky Butte rise to 614 feet (187 m) and 612 feet (187 m), respectively. To the west of the Tualatin Mountains lies the Oregon Coast Range, and to the east lies the actively volcanic Cascade Range. On clear days, Mt. Hood and Mt. St. Helens dominate the horizon, while Mt. Adams and Mt. Rainier can also be seen in the distance.
Document 6: Boston: Boston has an area of 89.6 square miles (232.1 km2)—48.4 square miles (125.4 km2) (54.0%) of land and 41.2 square miles (106.7 km2) (46.0%) of water. The city's official elevation, as measured at Logan International Airport, is 19 ft (5.8 m) above sea level. The highest point in Boston is Bellevue Hill at 330 feet (100 m) above sea level, and the lowest point is at sea level. Situated onshore of the Atlantic Ocean, Boston is the only state capital in the contiguous United States with an oceanic coastline.
Document 7: Oakland County International Airport: Oakland County International Airport is a county-owned public-use airport located in Waterford Township, Oakland County, Michigan, United States. The airport is located approximately 1 mile from the center of Waterford Township and Oakland County. It is included in the Federal Aviation Administration (FAA) National Plan of Integrated Airport Systems for 2017–2021, in which it is categorized as a non primary commercial service facility.
Document 8: Fremont Airport: Fremont Airport is a public-use airport located two nautical miles (4 km) southwest of the central business district of Fremont, a city in Sandusky County, Ohio, United States. It is privately owned by Fremont Airport LLC.
Document 9: Seattle: The city itself is hilly, though not uniformly so. Like Rome, the city is said to lie on seven hills; the lists vary, but typically include Capitol Hill, First Hill, West Seattle, Beacon Hill, Queen Anne, Magnolia, and the former Denny Hill. The Wallingford, Mount Baker, and Crown Hill neighborhoods are technically located on hills as well. Many of the hilliest areas are near the city center, with Capitol Hill, First Hill, and Beacon Hill collectively constituting something of a ridge along an isthmus between Elliott Bay and Lake Washington. The break in the ridge between First Hill and Beacon Hill is man-made, the result of two of the many regrading projects that reshaped the topography of the city center. The topography of the city center was also changed by the construction of a seawall and the artificial Harbor Island (completed 1909) at the mouth of the city's industrial Duwamish Waterway, the terminus of the Green River. The highest point within city limits is at High Point in West Seattle, which is roughly located near 35th Ave SW and SW Myrtle St. Other notable hills include Crown Hill, View Ridge/Wedgwood/Bryant, Maple Leaf, Phinney Ridge, Mt. Baker Ridge and Highlands/Carkeek/Bitterlake.
Document 10: Cheaha Mountain: Cheaha Mountain / ˈtʃiːhɔː /, often called Mount Cheaha, is the highest natural point in the U.S. state of Alabama. It is located a few miles northwest of the town of Delta in Cheaha State Park, which offers a lodge, a restaurant, and other amenities.
Document 11: Purdue University Airport: Purdue University Airport is a public-use airport in Tippecanoe County, Indiana, United States. Owned by Purdue University, the airport is southwest of the central business district of Lafayette, in West Lafayette. Because of the heavy traffic generated by Purdue University and its flight programs, Purdue University Airport is one of the busiest airports in Indiana, second only to Indianapolis International Airport.
Document 12: Cleveland Hopkins International Airport: Cleveland Hopkins International Airport (IATA: CLE, ICAO: KCLE, FAA LID: CLE) is a public airport located nine miles (14 km) southwest of the central business district of Cleveland, Cuyahoga County, Ohio, United States and adjacent to NASA's Glenn Research Center, one of NASA's ten major field centers. It is the primary airport serving Northeast Ohio, the largest and busiest airport in Ohio, and the 43rd busiest airport in the United States by passenger number. It is also the only airport in Ohio that offers nonstop transatlantic flights to Europe. Greater Cleveland is also served by Burke Lakefront Airport and Akron - Canton Regional Airport. Cleveland Hopkins and Cleveland Burke Lakefront Airport together comprise the Cleveland Airport System, operated by the City of Cleveland's Department of Port Control.
Document 13: Tennessee: The highest point in the state is Clingmans Dome at 6,643 feet (2,025 m). Clingmans Dome, which lies on Tennessee's eastern border, is the highest point on the Appalachian Trail, and is the third highest peak in the United States east of the Mississippi River. The state line between Tennessee and North Carolina crosses the summit. The state's lowest point is the Mississippi River at the Mississippi state line (the lowest point in Memphis, nearby, is at 195 ft (59 m)). The geographical center of the state is located in Murfreesboro.
Document 14: Orangeburg Municipal Airport: Orangeburg Municipal Airport is a city-owned, public-use airport located two nautical miles (4 km) south of the central business district of Orangeburg, a city in Orangeburg County, South Carolina, United States. It is included in the National Plan of Integrated Airport Systems for 2011–2015, which categorized it as a "general aviation" facility. The airport does not have scheduled commercial airline service.
Document 15: Bluffton Airport: Bluffton Airport is a public use airport located one nautical mile (1.85 km) southeast of the central business district of Bluffton, in Hancock County, Ohio, United States. It is owned by the Village of Bluffton. According to the FAA's National Plan of Integrated Airport Systems for 2009–2013, it is categorized as a "general aviation" facility.
ground_truth: Campbell Hill
sub_queries: In which state is Bluffton Airport located? Answer: Ohio
what is the highest point in the state of Ohio Answer: Campbell Hill