The given two tunnels are compared in terms of their in terms of their construction timelines, costs, dimensions, and structural designs in this diagram.
Overview, both tunnels share the same functional purposes, providing an efficient road transport in dual directions, but their distinct geographical locations and periods of construction account for the variations in cost, size, and complexity.
Glancing at the first chart, Tunnel A, constructed between 1987 and 1992, at a cost of $556 million, is 2,5 kilometres long and located 25 metres beneath the surface under the sea. It features twin tube layout, serving vehicles to travel in both directions. The tunnel was composed of stone and sand, possibly which suggests that it was built below the sea or river.
In contrast, Tunnel B, built from 2004 to 2007 is significantly longer at 3,6 kilometres and deeper, at 35 metres below ground. The profect cost nearly double, at $ 1,1 billion, reflecting the increased complexity of construction. Like Tunnel A, it employes a twin tube design in order to improve traffic. However Tunnel B appears to traverse more solid ground with the presence of water overhead.