Question: How far above the ground is the observation deck on the structure featured on the the Megastructures Season 4 Episode airing on 2008-05-20 ?

text: Megastructures
Episodes -- Season 4 ( 2007–2008 )

Megastructures is a documentary television series appearing on the National Geographic Channel in the United States and the United Kingdom, Channel 5 in the United Kingdom, France 5 in France, and 7mate in Australia. Each episode is an educational look of varying depth into the construction, operation, and staffing of various structures or construction projects, but not ordinary construction products. Generally containing interviews with designers and project managers, it presents the problems of construction and the methodology or techniques used to overcome obstacles. In some cases (such as the Akashi-Kaikyo Bridge and Petronas Towers) this involved the development of new materials or products that are now in general use within the construction industry. Megastructures focuses on constructions that are extreme; in the sense that they are the biggest, tallest, longest, or deepest in the world. Alternatively, a project may appear if it had an element of novelty or are a world first (such as Dubai's Palm Islands). This type of project is known as a megaproject. The series follows similar subjects as the History Channel's Modern Marvels and Discovery Channel's Extreme Engineering, covering areas of architecture, transport, construction and manufacturing.
# Country Title Subject Original Airdate
01 United Arab Emirates World 's Tallest Hotel Burj al-Arab Hotel in Dubai , United Arab Emirates 2007-07-09
02 Malaysia SMART Tunnel SMART Tunnel for road and storm water drainage in Kuala Lumpur to relieve traffic congestion as well as to prevent flooding within the city 2007-07-14
03 Bermuda RMS Queen Mary 2  2007-07-16
04 United States South Pole Station A science facility at the South Pole ( Amundsen-Scott South Pole Station ) 2007-11-06
05 China Beijing Water Cube Beijing National Aquatics Center built for the 2008 Beijing Summer Olympics 2008-05-13
06 United States Bridge Breakdown Demolition of the ( 1927 ) Carquinez Bridge in the San Francisco Bay Area 2008-05-15
07 United States 747 Destruction Evergreen Air Center storage facility for decommissioned aeroplanes in Marana , Arizona 2008-05-16
08 China Shanghai Super Tower Shanghai World Financial Centre in Shanghai , China 2008-05-20
09 China China 's Ultimate Port Yangshan Port in Hangzhou Bay 2008-05-27
10 United States Sinking an aircraft carrier Creating the world 's largest artificial reef with USS Oriskany in the Gulf of Mexico off Florida 2008-05-29
11 Finland The World 's Biggest Cruise Liner The building of cruise liner MS Freedom of the Seas 2008-06-04
12 China Beijing Olympic Stadium the building of the main stadium for the 2008 Beijing Summer Olympics 2008-08-05
13 China World 's Biggest Casino The Venetian Macao , the world 's biggest casino in Macau ?
14 Iceland Icelandic Super Dam The building of the Kárahnjúkar Hydropower Plant , Europe 's biggest dam in Iceland ?
15 Germany Future Trains Maglev train ?
16 United Arab Emirates Building the World The World ( archipelago ) of artificial islands in Dubai ?
17 United States Train Wreck the recycling of obsolete train locomotives in the USA ?
18 China Building Green Beijing 2010 environmental improvement plan in Beijing , China ?
19 France Switzerland Atom Smasher The Large Hadron Collider at CERN near Geneva , Switzerland ?
20 China Impossible Bridges : China Lupu Bridge in Shanghai , Runyang Bridge in Jiangsu Province , and Sutong Bridge near Suzhou ?