Question: How old do you have to be to buy a handgun in US state having Riverfront Parkway?

full_context: Document 1: Duck Creek (Quad Cities): Duck Creek is a minor tributary of the Mississippi River in the United States. The creek runs through Scott County, Iowa, and the cities of Davenport, Bettendorf, and Riverdale.
Document 2: Great River Road: The Great River Road is a collection of state and local roads that follow the course of the Mississippi River through ten states of the United States. They are Minnesota, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi and Louisiana. It formerly extended north into Canada, serving the provinces of Ontario and Manitoba.
Document 3: Gun laws in Michigan: At the age of 18 or up, it is legal to buy a pistol with a purchase license from a private seller, at the age of 21, it is legal to buy a firearm from a Federally licensed (FFL) dealer. No purchase license is required to purchase a long gun (a firearm that is more than 26 inches long) in Michigan. According to state law, a long gun may be purchased by anyone aged 18 or over who is not subject to restrictions based on criminal history, mental health history, or other disqualifying factor. A person must be at least 18 years old to purchase a long gun from a federal dealer or a private seller under Michigan law.
Document 4: Richmond, Virginia: There are also parks on two major islands in the river: Belle Isle and Brown's Island. Belle Isle, at various former times a Powhatan fishing village, colonial-era horse race track, and Civil War prison camp, is the larger of the two, and contains many bike trails as well as a small cliff that is used for rock climbing instruction. One can walk the island and still see many of the remains of the Civil War prison camp, such as an arms storage room and a gun emplacement that was used to quell prisoner riots. Brown's Island is a smaller island and a popular venue of a large number of free outdoor concerts and festivals in the spring and summer, such as the weekly Friday Cheers concert series or the James River Beer and Seafood Festival.
Document 5: Riverfront Parkway: Riverfront Parkway is located along the Mississippi River in the cities of Davenport and Bettendorf in the U.S. state of Iowa. The parkway is a bike and walking trail that extends for 11 miles (17.7 km) starting at Credit Island on the west passing through Davenport for 7.6 miles (12.2 km) before entering Bettendorf. It continues for another 3.4 miles (5.47 km) at its terminus on the east side of Bettendorf. On Credit Island the bike path circles the park for 2.62 miles (4.22 km). On its way east from Credit Island it passes through Veterans Memorial Park, which is being developed, Centennial Park, LeClaire Park, River Heritage Park that is being developed on the east side of downtown Davenport, and Lindsay Park. In Bettendorf it passes through Leach Park. There are plans to connect the park to the Duck Creek Parkway and Sunderbruch Park in the future. There are public art installations along the parkway at Credit Island, Lindsay Park and Leach Park.
Document 6: Detroit: Campus Martius, a reconfiguration of downtown's main intersection as a new park was opened in 2004. The park has been cited as one of the best public spaces in the United States. The city's riverfront has been the focus of redevelopment, following successful examples of other older industrial cities. In 2001, the first portion of the International Riverfront was completed as a part of the city's 300th anniversary celebration, with miles of parks and associated landscaping completed in succeeding years. In 2011, the Port Authority Passenger Terminal opened with the river walk connecting Hart Plaza to the Renaissance Center.
Document 7: Gun laws in Arizona: Arizona gun laws are found mostly in Title 13, Chapter 31 of the Arizona Revised Statutes. There is no registration or licensing of non-NFA firearms in Arizona. Section 13 - 3108 subsection B prohibits any political subdivision of the state from enacting any laws requiring licensing or registration. According to state law, a person must be 18 years of age to purchase any non-NFA firearm from any source; however, there is a federal age limit of 21 years on handgun purchases from federal firearms licensees.
Document 8: Gun laws in Tennessee: A license is required to carry a loaded handgun either openly or concealed. Such permits are issued through the Department of Safety to qualified residents 21 years or 18 years old if the applicant is active duty, reservist, guardsman, or honorably discharged from their branch of service, DD - 214 must mention 'pistol qualification' in order to be exempt from 8 hour safety course must have a valid military ID. The length of the term for the initial license is determined by the age of the applicant. If renewed properly and on time, the license is renewed every 5 years. Tennessee recognizes any valid, out - of - state permit for carrying a handgun as long as the permittee is not a resident of Tennessee. Nonresidents are not issued permits unless they are regularly employed in the state. Such persons are then required to obtain Tennessee permits even if they have home state permits unless their home state has entered into a reciprocity agreement with Tennessee. Permittees may carry handguns in most areas except civic centers, public recreation buildings and colleges. Businesses or landowners posting ``no carry ''signs may prohibit gun carry on any portion of their properties.
Document 9: San Antonio River Walk: The River Walk is a successful special - case pedestrian street, one level down from the automobile street. The River Walk winds and loops under bridges as two parallel sidewalks lined with restaurants and shops, connecting the major tourist draws from the Shops at Rivercenter, to the Arneson River Theatre, to Marriage Island, to La Villita, to HemisFair Park, to the Tower Life Building, to the San Antonio Museum of Art, to the Pearl and the city's five Spanish colonial missions, which have been named a World Heritage Site, including the Alamo. During the annual springtime Fiesta San Antonio, the River Parade features flowery floats that float down the river.
Document 10: Gun laws in Indiana: Indiana is a ``shall issue ''state for the License To Carry a Handgun. A license to carry will be issued to individuals age 18 or older who meet a number of legal requirements. Currently both limited term and unlimited lifetime licenses are available.
Document 11: Gun laws in Ohio: In April 2004, Ohio became the 46th state to legalize concealed carry and its statute went into effect. The law (Ohio Revised Code (O.R.C.) 2923.12, et seq.) allows persons 21 and older to receive a concealed handgun license provided that they receive a minimum of 8 hours of handgun training (6 hours of classroom instruction and 2 hours of range time) from a certified instructor, demonstrate competency with a handgun through written and shooting tests, pass a criminal background check, and meet certain residency requirements (non-residents who work in Ohio will be allowed to obtain licenses as of March 23, 2015).
Document 12: Charles River Reservation Parkways: The Charles River Reservation Parkways are parkways that run along either side of the Charles River in eastern Massachusetts. The roads are contained within the Charles River Reservation and the Upper Charles River Reservation, and fall within a number of communities in the greater Boston metropolitan area. The Charles River parks extend from the Charles River Dam, where the Charles empties into Boston Harbor, to Riverdale Park in the West Roxbury neighborhood of Boston. Most of the roadways within the parks are listed on the National Register of Historic Places as a unit, although Storrow Drive and Memorial Drive are listed as part of the Charles River Basin Historic District.
Document 13: Gun laws in Washington: As a general rule, a person may legally open - carry in Washington state in any place it is legal to possess a loaded handgun, as long as it does not manifest ``an intent to intimidate another or (warrant) alarm for the safety of other persons. ''To open - carry a handgun in a vehicle (e.g, car, bus, etc...) a person must have a valid concealed pistol license. The county sheriff or city police chief shall issue a concealed pistol license to any applicant, age 21 or older, who meets certain requirements, including no felony convictions, no misdemeanor domestic violence convictions, and no outstanding warrants. Open carrying of firearms is not prohibited by law, although trouble with some law enforcement agencies has been encountered while open carrying in the past, most notably in a case in Ellensburg, Washington.
Document 14: Gun laws in Iowa: A Permit To Acquire (PTA), obtained from the sheriff of the county of the applicant's residence, is required when purchasing or otherwise acquiring a handgun, either from a dealer or from a private party. A Permit To Acquire shall be issued to qualified applicants aged 21 or older. The PTA becomes valid three days after the date of application, and is valid for one year. A PTA is not required when purchasing an antique handgun, defined as one made in or before 1898 and including post-1898 replicas of matchlock, flintlock, or percussion cap pistols.
Document 15: Detroit: The Detroit International Riverfront includes a partially completed three-and-one-half mile riverfront promenade with a combination of parks, residential buildings, and commercial areas. It extends from Hart Plaza to the MacArthur Bridge accessing Belle Isle Park (the largest island park in a U.S. city). The riverfront includes Tri-Centennial State Park and Harbor, Michigan's first urban state park. The second phase is a two-mile (3 km) extension from Hart Plaza to the Ambassador Bridge for a total of five miles (8 km) of parkway from bridge to bridge. Civic planners envision that the pedestrian parks will stimulate residential redevelopment of riverfront properties condemned under eminent domain.
ground_truth: 21 or older.
sub_queries: Which state is Riverfront Parkway located? Answer: Iowa
how old do you have to be to buy a handgun in Iowa Answer: 21 or older.