Q:Information: - The Willamette River is a major tributary of the Columbia River, accounting for 12 to 15percent of the Columbia's flow. The Willamette's main stem is long, lying entirely in northwestern Oregon in the United States. Flowing northward between the Oregon Coast Range and the Cascade Range, the river and its tributaries form the Willamette Valley, a basin that contains two-thirds of Oregon's population, including the state capital, Salem, and the state's largest city, Portland, which surrounds the Willamette's mouth at the Columbia. - A county seat is an administrative center, seat of government, or capital city of a county or civil parish. The term is used in the United States, Canada, Romania, China and Taiwan. In the United Kingdom and Ireland, county towns have a similar function. - Oregon Route 221 is an Oregon state highway which runs between the city of Salem, Oregon and the city of Dayton, Oregon, roughly along the western shore of the Willamette River. It is known as the Salem-Dayton Highway No. 150 (see Oregon highways and routes), and is long. It lies in the counties of Yamhill and Polk County. - A tributary or affluent is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage basin of its surface water and groundwater, leading the water out into an ocean. - The Eola Hills are a range of hills northwest of Salem, Oregon, United States. They stretch from the community of Eola about north to Yamhill County. - A state highway, state road, or state route (and the equivalent provincial highway, provincial road, or provincial route) is usually either a road "numbered" by the state or province, falling below numbered national highways in the hierarchy (route numbers are used to aid navigation, and may or may not indicate ownership or maintenance); or a road "maintained" by the state or province, including both nationally numbered highways and un-numbered state highways. Depending on the state, state highway may be used for one meaning and state road or state route for the other. - The Oregon Coast Range, often called simply the Coast Range and sometimes the Pacific Coast Range, is a mountain range, in the Pacific Coast Ranges physiographic region, in the U.S. state of Oregon along the Pacific Ocean. This north-south running range extends over from the Columbia River in the north on the border of Oregon and Washington, south to the middle fork of the Coquille River. It is wide and averages around in elevation above sea level. The coast range has three main sections, a Northern, Central, and Southern. - The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades. The small part of the range in British Columbia is referred to as the Canadian Cascades or, locally, as the Cascade Mountains. The latter term is also sometimes used by Washington residents to refer to the Washington section of the Cascades in addition to North Cascades, the more usual U.S. term, as in North Cascades National Park. The highest peak in the range is Mount Rainier in Washington at . - A valley is a low area between hills, often with a river running through it. - Spring Valley is a valley in Polk County , Oregon , United States , situated north and east of the Eola Hills and west of the Willamette River . It corresponds roughly to the drainage of Spring Valley Creek . Populated places in Spring Valley include Zena and Lincoln . Oregon Route 221 passes along the east side of the valley , next to the Willamette River . The area is in the Eola - Amity Hills AVA wine region and is home to several notable vineyards , including Cristom . - A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases a river flows into the ground and becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to using names such as stream, creek, brook, rivulet, and rill. There are no official definitions for the generic term river as applied to geographic features, although in some countries or communities a stream is defined by its size. Many names for small rivers are specific to geographic location; examples are "run" in some parts of the United States, "burn" in Scotland and northeast England, and "beck" in northern England. Sometimes a river is defined as being larger than a creek, but not always: the language is vague. - The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada. It flows northwest and then south into the US state of Washington, then turns west to form most of the border between Washington and the state of Oregon before emptying into the Pacific Ocean. The river is long, and its largest tributary is the Snake River. Its drainage basin is roughly the size of France and extends into seven US states and a Canadian province. - "Main Stem" is 1942 instrumental by Duke Ellington and His Famous Orchestra. Although recorded in 1942, the single would not be released until 1944 where it was Duke Ellington's last of four number one's on the Harlem Hit Parade. "Main Stem" also peaked at number twenty on the pop chart. - Salem is the capital of the U.S. state of Oregon, and the county seat of Marion County. It is located in the center of the Willamette Valley alongside the Willamette River, which runs north through the city. The river forms the boundary between Marion and Polk counties, and the city neighborhood of West Salem is in Polk County. Salem was founded in 1842, became the capital of the Oregon Territory in 1851, and was incorporated in 1857. - Dayton is a city in Yamhill County, Oregon, United States. The population was 2,534 at the 2010 census. - A census is the procedure of systematically acquiring and recording information about the members of a given population. It is a regularly occurring and official count of a particular population. The term is used mostly in connection with national population and housing censuses; other common censuses include agriculture, business, and traffic censuses. The United Nations defines the essential features of population and housing censuses as "individual enumeration, universality within a defined territory, simultaneity and defined periodicity", and recommends that population censuses be taken at least every 10 years. United Nations recommendations also cover census topics to be collected, official definitions, classifications and other useful information to co-ordinate international practice. - A U.S. state is a constituent political entity of the United States of America. There are 50 states, which are bound together in a union with each other. Each state holds administrative jurisdiction over a defined geographic territory, and shares its sovereignty with the United States federal government. Due to the shared sovereignty between each state and the federal government, Americans are citizens of both the federal republic and of the state in which they reside. State citizenship and residency are flexible, and no government approval is required to move between states, except for persons covered by certain types of court orders (e.g., paroled convicts and children of divorced spouses who are sharing custody). - Polk County is a county located in the U.S. state of Oregon. As of the 2010 census, the population was 75,403. The county seat is Dallas. The county is named for James Knox Polk, the 11th president of the United States. Given the information, choose the subject and object entities that have the relation of 'part of'.
A:
spring valley , willamette valley