Question:
Def Leppard are an English rock band formed in 1977 in Sheffield as part of the new wave of British heavy metal movement. Since 1992, the band has consisted of Joe Elliott (lead vocals), Rick Savage (bass, backing vocals), Rick Allen (drums, backing vocals), Phil Collen (lead and rhythm guitar, backing vocals), and Vivian Campbell (rhythm and lead guitar, backing vocals). This is the band's longest lasting line-up. The band's strongest commercial success came between the early 1980s and the early 1990s.
Rick Savage, Tony Kenning, and Pete Willis, all students at Tapton School in Sheffield, South Yorkshire, formed a band called Atomic Mass in 1977. The band originally consisted of Willis on guitar, Savage on bass (after originally playing guitar), and Kenning on drums. Only 18 at the time, Joe Elliott tried out for the band as a guitarist following a chance meeting with Willis after missing a bus, in November 1977. During his audition it was decided that he was better suited to be the lead singer. Their first ever gig was in the dining hall in A Block in Westfield School in Mosborough, Sheffield.  The band adopted a name proposed by Elliott, "Deaf Leopard", which was originally a band name he thought up while writing reviews for imaginary rock bands in his English class (and in at least partial reference to Led Zeppelin). At Kenning's suggestion, the spelling was slightly modified in order to make the name seem less like that of a punk band. In January 1978, Steve Clark joined the band. According to Elliott, he successfully auditioned for the band by playing Lynyrd Skynyrd's "Free Bird" in its entirety.  In November, just prior to recording sessions for what would be a three-song release known as The Def Leppard E.P., Kenning abruptly left the band; he would later form the band Cairo. He was replaced for those sessions by Frank Noon. By the end of the month, Rick Allen, then only 15 years old, had joined the band as its full-time drummer. Sales of the EP soared after the track "Getcha Rocks Off" was given extensive airtime by renowned BBC Radio 1 DJ John Peel, considered at the time to be a champion of punk rock and new wave music.  Throughout 1979, the band developed a loyal following among British hard rock and heavy metal fans and were considered among the leaders of the new wave of British heavy metal movement. Their growing popularity led to a record deal with the major label Phonogram/Vertigo (Mercury Records in the US). Def Leppard's original management, MSB, a local duo consisting of Pete Martin and Frank Stuart-Brown, were fired after Martin and Joe Elliott got into a fistfight over an incident on the road. The band approached Peter Mensch of Leber-Krebs management, who had booked them on a tour of the UK supporting AC/DC. Mensch, who admitted that he had had his eye on the band, became their manager.
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Where did the band members first meet?

Answer:
Rick Savage, Tony Kenning, and Pete Willis, all students at Tapton School in Sheffield, South Yorkshire,

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Fazlur Rahman Khan (Bengali: phjlur rhmaan khaan, Fozlur Rohman Khan) (3 April 1929 - 27 March 1982) was a Bangladeshi-American structural engineer and architect, who initiated important structural systems for skyscrapers. Considered the "father of tubular designs" for high-rises, Khan was also a pioneer in computer-aided design (CAD). He was the designer of the Sears Tower, since renamed Willis Tower, the tallest building in the world from 1973 until 1998, and the 100-story John Hancock Center. Khan, more than any other individual, ushered in a renaissance in skyscraper construction during the second half of the 20th century.
Khan's central innovation in skyscraper design and construction was the idea of the "tube" structural system for tall buildings, including the framed tube, trussed tube, and bundled tube variants. His "tube concept", using all the exterior wall perimeter structure of a building to simulate a thin-walled tube, revolutionized tall building design. Most buildings over 40 stories constructed since the 1960s now use a tube design derived from Khan's structural engineering principles.  Lateral loads (horizontal forces) such as wind forces, seismic forces, etc., begin to dominate the structural system and take on increasing importance in the overall building system as the building height increases. Wind forces become very substantial, and forces caused by earthquakes, etc. are important as well. The tubular designs resist such forces for tall buildings. Tube structures are stiff and have significant advantages over other framing systems. They not only make the buildings structurally stronger and more efficient, but also significantly reduce the structural material requirements. The reduction of material makes the buildings economically more efficient and reduces environmental impact. The tubular designs enable buildings to reach even greater heights. Tubular systems allow greater interior space and further enable buildings to take on various shapes, offering added freedom to architects. These new designs opened an economic door for contractors, engineers, architects, and investors, providing vast amounts of real estate space on minimal plots of land. Khan was among a group of engineers who encouraged a rebirth in skyscraper construction after a hiatus of over thirty years.  The tubular systems have yet to reach their limit when it comes to height. Another important feature of the tubular systems is that buildings can be constructed using steel or reinforced concrete, or a composite of the two, to reach greater heights. Khan pioneered the use of lightweight concrete for high-rise buildings, at a time when reinforced concrete was used for mostly low-rise construction of only a few stories in height. Most of Khan's designs were conceived considering pre-fabrication and repetition of components so projects could be quickly built with minimal errors.  The population explosion, starting with the baby boom of the 1950s, created widespread concern about the amount of available living space, which Khan solved by building upward. More than any other 20th-century engineer, Fazlur Rahman Khan made it possible for people to live and work in "cities in the sky." Mark Sarkisian (Director of Structural and Seismic Engineering at Skidmore, Owings & Merrill) said, "Khan was a visionary who transformed skyscrapers into sky cities while staying firmly grounded in the fundamentals of engineering."

Do they still use this system today?
Most buildings over 40 stories constructed since the 1960s now use a tube design