Arrange the following continents in descending order of their total operational railway route length (highest to lowest): 1. North America 2. Europe 3. Asia 4. Africa

With reference to the Trans-Siberian Railway, consider the following statements: (a) It connects Russia’s western regions with the Pacific coast. (b) It is entirely single-tracked and non-electrified. (c) It has facilitated the export of resources from Asian Russia to European markets. (d) It crosses major river systems including the Ob and Yenisei. Which of the statements given above are correct?

Arrange the following transport systems in increasing order of their typical initial infrastructure installation costs per kilometer (lowest to highest): 1. Pipelines 2. Road transport 3. Railways 4. Airways