Definition: In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Input: Passage: Oklahoma is between the Great Plains and the Ozark Plateau in the Gulf of Mexico watershed, generally sloping from the high plains of its western boundary to the low wetlands of its southeastern boundary. Its highest and lowest points follow this trend, with its highest peak, Black Mesa, at 4,973 feet (1,516 m) above sea level, situated near its far northwest corner in the Oklahoma Panhandle. The state's lowest point is on the Little River near its far southeastern boundary near the town of Idabel, which dips to 289 feet (88 m) above sea level.
Among the most geographically diverse states, Oklahoma is one of four to harbor more than 10 distinct ecological regions, with 11 in its borders—more per square mile than in any other state. Its western and eastern halves, however, are marked by extreme differences in geographical diversity: Eastern Oklahoma touches eight ecological regions and its western half contains three. Although having fewer ecological regions Western Oklahoma contains many rare, relic species.
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 are 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, The Oklahoma Tourism & Recreation Department regards Cavanal Hill as the world's tallest hill; at 1,999 feet (609 m), it fails their definition of a mountain by one foot.The semi-arid high plains in the state's northwestern corner harbor few natural forests; the region has a rolling to flat landscape with intermittent canyons and mesa ranges like the Glass Mountains. Partial plains interrupted by small, sky island mountain ranges like the Antelope Hills and the Wichita Mountains dot southwestern Oklahoma; transitional prairie and oak savannas cover the central portion of the state. The Ozark and Ouachita Mountains rise from west to east over the state's eastern third, gradually increasing in elevation in an eastward direction.
 
More than 500 named creeks and rivers make up Oklahoma's waterways, and with 200 lakes created by dams, it holds the nation's highest number of artificial reservoirs. Most of the state lies in two primary drainage basins belonging to the Red and Arkansas rivers, though the Lee and Little rivers also contain significant drainage basins.
Output:
What is Oklahoma's lowest point in terms of feet?