Amu Darya

                 Amu Darya (Amudaryo, Oxos, Амударё ,آمودریا) is a major river in Central Asia. It is formed by the junction of the Vakhsh and Panj rivers. The river's total length is 2,400 kilometres (1,500 mi) The river is navigable for over 1,450 kilometres (900 mi). All of the water comes from the high mountains in the south where annual precipitation can be over 1,000 mm (39 in). 
                 The main tributaries of Amu Darya are: Panj River, Vakhsh River, Surkhan Darya, Sherabad River, Zeravshan River. Use of water from the Amu Darya for irrigation has been a major contributing factor to the shrinking of the Aral Sea since the late 1950s.

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Populus

                 Populus is a genus of 25–35 species of deciduous flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar, aspen, and cottonwood. The genus has a large genetic diversity, and can grow from anywhere between 15–50 m (50 to 165 ft) tall, with trunks of up to 2.5 m (8 ft) diameter. 
                 The genus Populus has traditionally been divided into six sections on the basis of leaf and flower characters. These are: Populus section Populus – aspens and White Poplar, Populus section Aigeiros – black poplars, some of the cottonwoods, Populus section Tacamahaca – balsam poplars, Populus section Leucoides – necklace poplars or bigleaf poplars, Populus section Turanga – subtropical poplars, Populus section Abaso – Mexican poplars.

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Lake Tanganyika

                Lake Tanganyika is an African Great Lake. It is estimated to be the second largest freshwater lake in the world by volume, and the second deepest, in both cases, after only Lake Baikal in Siberia. It had a surface of 32,900 km2 (12,700 sq mi). It is also the world's longest freshwater lake. The lake is divided among four countries – Tanzania, the Democratic Republic of the Congo, Burundi, and Zambia. 
                The major river that flows into this lake is the Ruzizi River, which enters the north of the lake from Lake Kivu. The Malagarasi River, which is Tanzania's second largest river, enters the east side of Lake Tanganyika. The Malagarasi is older than Lake Tanganyika and before the lake was formed directly drained into the Congo river .

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Great hammerhead shark

               Great hammerhead (Sphyrna mokarran) is the largest species of hammerhead shark, family Sphyrnidae, attaining a maximum length of 6.1 m (20 ft). It is found in tropical and warm temperate waters worldwide, inhabiting coastal areas and the continental shelf. 
                An active predator with a varied diet, known prey of the great hammerhead include invertebrates such as crabs, lobsters, squid, and octopus, bony fishes such as tarpon, sardines, sea catfishes, toadfish, porgies, grunts, jacks, croakers, groupers, flatfishes, boxfishes, and porcupine fishes, and smaller sharks such as smoothhounds.
                 With its large size and cutting teeth, the great hammerhead is certainly capable of inflicting fatal injuries to a human and caution should be exercised around them. This species has a (possibly undeserved) reputation for aggression and being the most dangerous of the hammerhead sharks.

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Arkansas River

                Arkansas River is a major tributary of the Mississippi River. The Arkansas generally flows to the east and southeast as it traverses the US states of Colorado, Kansas, Oklahoma, and Arkansas. At 2,364 km (1,469 miles) it is the sixth-longest river in the United States, the second-longest tributary in the Mississippi–Missouri system, and the 45th longest river in the world. Its origin is in the Rocky Mountains in Lake County, Colorado, near Leadville. 
               The main tributaries are: Fountain Creek, Pawnee River, Verdigris River, Neosho River, Cimarron River, Canadian River, Poteau River. Arkansas river is flowing through Pueblo, Wichita, Tulsa, Muskogee, Fort Smith, Little Rock, Pine Bluff.

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Mount Rainier

                 Mount Rainier is a massive stratovolcano located 54 miles (87 km) southeast of Seattle in the state of Washington, United States. It is the most topographically prominent mountain in the contiguous United States and the Cascade Volcanic Arc, with a summit elevation of 14,411 ft (4,392 m). On clear days it dominates the southeastern horizon in most of the Seattle-Tacoma metropolitan area to such an extent that locals sometimes refer to it simply as "the Mountain." On days of exceptional clarity, it can also be seen from as far away as Portland, Oregon and Victoria, British Columbia. It had an elevation of 4,392 m (14,411 ft). 
                 With 26 major glaciers and 36 sq mi (93 km2) of permanent snowfields and glaciers, Mount Rainier is the most heavily glaciated peak in the lower 48 states. The Carbon, Puyallup, Mowich, Nisqually, and Cowlitz Rivers begin at eponymous glaciers of Mount Rainier. 

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