```If you don’t own Black Panther Pursuit or any of the sets that included Captain America, I guess it would a plus getting the both of them in this set but Super Heroes collectors tend to be completionists, so I think that scenario will be particularly rare. I guess you could always sell your spares on the secondary market, but really, who wants to do that?
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In December 2012, the BBC's More or Less radio program asked the Open University's engineering department to determine "how many Lego bricks, stacked one on top of the other, it would take for the weight to destroy the bottom brick?"[44] Using a hydraulic testing machine, the engineering department determined the average maximum force a 2×2 Lego brick can stand is 4,240 newtons; since an average 2×2 Lego brick has a mass of 1.152 grams (0.0406 oz), according to their calculations it would take a stack of 375,000 bricks to cause the bottom brick to collapse, which represents a stack 3,591 metres (11,781 ft) in height.[44]

# Lego pieces of all varieties constitute a universal system. Despite variation in the design and the purposes of individual pieces over the years, each piece remains compatible in some way with existing pieces. Lego bricks from 1958 still interlock with those made in the current time, and Lego sets for young children are compatible with those made for teenagers. Six bricks of 2 × 4 studs[28] can be combined in 915,103,765 ways.[29]

Inside the box we find eight numbered bags, two unnumbered bags containing large molded plane parts, two loose 16x16 plates, the large airplane wing in medium grey, a sticker sheet and four instruction booklets of varying sizes. Unfortunately there is no cardboard to keep the booklets and sticker sheet flat (though fortunately mine were not crumpled), but never fear, there is a brick separator!
LEGO City enables us all to remember why we fell in love with LEGO to begin with, to remember how we all first became exposed to LEGO; as a little kid, building our first house or giving our minifigures a hospital or a police station to work in. My first set was a garage, quickly followed by a police station. Having recently found these in storage, and keen to rebuild them, having the opportunity to build something not revolving around a Jedi or an Avenger is one I keen to take advantage of.

Bag 6 starts the airport terminal.  Like most CITY builds, they are meant for play so it's really only half a building.  It includes one minifigure and the revolving door entrance.  While the entrance is cool looking, it's about twice the height of a minifigure and there isn't enough physical space for one actually to fit through the door.  I'm not a fan of the design.