The atoms that make up a molecule can be of the same element or different types. Diatomic molecules are a specific class of molecules that consist of two molecules of the same element. If the molecule is composed of atoms of at least two different elements, it is a chemical compound.
The cost of light rail construction varies widely, largely depending on the amount of tunneling and elevated structures required. A survey of North American light rail projects shows that costs of most LRT systems range from $15 million to over $100 million per mile.he cost of 17 miles (27 km) of highway improvements and 19 miles (31 km) of double-track light rail worked out to $19.3 million per highway lane-mile and $27.6 million per LRT track-mile. The project came in under budget and 22 months ahead of schedule.
Reference to this paper should be made as follows: Rui, Z., Metz, P.A., Reynolds, D., Chen, G. and Zhou, X. (2011) âHistorical pipeline construction cost analysisâ, Int. J. Oil, Gas and Coal Technology, Vol. 4, No. 3, pp.244â263.n this section, the trend of unit component costs of pipeline over time is analysed. Unit cost is calculated by dividing cost by volume. For all 412 pipelines, the average unit cost in material, labour, miscellaneous, ROW and total cost were $18/ft3, $24/ft3, $14/ft3, $5/ft3 and $61/ft3 respectively.