Parts of the teeth include: 1  Enamel: The hardest, white outer part of the tooth. Enamel is mostly made of calcium phosphate, a rock-hard mineral. 2  Dentine: A layer underlying the enamel. Dentine is made of living cells, which secrete a hard mineral substance.  Pulp: The softer, living inner structure of teeth.
Though they vary significantly, transportation costs accounted for 40% of the average overall cost of coal delivered at electric power plants in 2010. On average, nominal U.S. rail rates for shipping coal grew from $11.83 to $17.25 per short ton from 2001 to 2010.
CUTA also reports that the average cost of public transit in Canada is $2.59 per ride and $68.24 for a monthly pass. Below are costs for rides and monthly passes in major cities and provinces across Canada, provided by CUTA, to give you an idea of the cost of commuting by using transit.