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 $27.6 million per LRT track-mile. The project came in under budget and 22 months ahead of schedule.
Chinaâs high speed rail with a maximum speed of 350 km/h has a typical infrastructure unit cost of about US$ 17-21m per km, with a high ratio of viaducts and tunnels, as compared with US$25-39 m per km in Europe and as high as US$ 56m per km currently estimated in California.elicious. æ°æµªå¾®å. BEIJING, July 10, 2014 â By the end of 2013, China had built a high speed rail[1] network of over 10,000 route-km, far exceeding that in any other country and larger than the network in the entire European Union. It has been accomplished at a cost which is at most two-thirds of that in other countries.