Question: Which health chain operates much of the amenity space in Sky, a luxury tower in Manhattan?

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Fish wheel: A fish wheel is a device for catching fish which operates much as a water-powered mill wheel.  A wheel complete with baskets and paddles is situated on the river, usually upon a floating dock.  The wheel rotates due to the current of the stream pressing the bottom basket or paddle that has swung down into the water.  The baskets on the wheel, swinging downstream only at the speed of the current or more slowly, capture fish actively swimming upstream and also can capture fish simply drifting.

Sookerating Air Force Station: Sookerating Air Force Station is an Indian Air Force base located at Sookerating in the state of Assam, India.  It is a secondary airport for the Indian Air Force, which operates much more actively from other air bases in the region. .

Waterline Square: Waterline Square is a 5 acre , $2.3 billion luxury condominium and rental development located near the Hudson River on the Upper West Side of New York City.  The complex will include three residential towers and 3 acre of park, along with 100000 sqft of amenity space.  The residences range in size from one to five bedrooms.

399 Fremont Street: 399 Fremont Street is a 122 m residential skyscraper in the Rincon Hill neighborhood of San Francisco, California.  The tower has 447 residential units on 42 floors, and 25,000 square feet of amenity space.

Life Time Fitness: Life Time Fitness is a chain of health clubs in the United States and Canada.  Many of its facilities operate 24/7 and feature personal trainers, salons, food courts, child care centers, and indoor/outdoor pools.

Hawaiian sling: The Hawaiian sling is a device used in spearfishing.  The sling operates much like a bow and arrow does on land, but energy is stored in rubber tubing rather than a wooden or fiberglass bow.

DP-64: The DP-64 Nepryadva is a Russian special-purpose double-barreled over/under grenade launcher designed to protect ships, dockyards, water development works, and other coastal installations from combat swimmers and naval special forces.  The weapon is breech-loading and operates much like a large shotgun with a side-break breach, utilizing both direct and indirect iron sights.  The weapon is capable of firing grenades indirectly at ranges up to 400 meters; however, these grenades act much like small depth charges, attacking submerged swimmers like true depth charges attack submersibles.  A large polymer stock and the barrels themselves makes up the bulk of the weapon.  The barrels are selected by turning a lever accommodated above the trigger guard.  A front pistol grip is equipped for support and is out of alignment with the rear grip and trigger mechanism, providing a more natural grip while firing indirectly.  The butt is fitted with a springy rubber pad used to diminish felt recoil.  Direct fire sights are also provided for use from a helicopter allowing for large areas to be patrolled and protected from enemy combat swimmers.  The grenade launcher was developed in 1989 and introduced in 1990.

Amenity: In real estate and lodging, an amenity is something considered to benefit a property and thereby increase its value.  Tangible amenities can include the number and nature of guest rooms and the provision of facilities such as elevators (lifts), wi-fi, restaurants, parks, communal areas, swimming pools, golf courses, health club facilities, party rooms, theater or media rooms, bike paths or garages, while intangible amenities can include aspects such as well-integrated public transport, pleasant views, nearby activities and a low crime rate.  Within the context of environmental economics, an environmental amenity can include access to clean air or clean water, or the quality of any other environmental good that may reduce adverse health effects for residents or increase their economic welfare.

Sky (skyscraper): Sky, also known as 605 West 42nd Street, is a mixed-use building in Midtown Manhattan developed by the Moinian Group.  The 71-story tower contains luxury rental residences designed by the Rockwell Group, ranging from studios to two bedrooms and includes the Vue Penthouse Collection.  Sky features over 70,000 square feet of amenity space, mostly operated by Life Time Fitness, which includes a multi-level gym, water club and LifeSpa, lap pool, professional size basketball court (designed by Carmelo Anthony), two outdoor zero edge pools, and an outdoor park.  The building also contains retail space.  The building’s architect was Goldstein, Hill & West Architects.

Nibbler: A nibbler, or nibblers, is a tool for cutting sheet metal with minimal distortion.  One type operates much like a punch and die, with a blade that moves in a linear fashion against a fixed die, removing small bits of metal and leaving a kerf approximately 6 mm wide.  Another type operates similar to tin snips, but shears the sheet along two parallel tracks 3–6 mm apart, rolling up the waste in a tight spiral as it cuts.  Nibblers may be manual (hand operated) or powered.

Supporting paragraphs: Sky (skyscraper) Life Time Fitness
Answer: Life Time Fitness