A Model for How Long Our Coal Resources Will Last

Multiple Choice

A model for how long our coal resources will last is given by where r is the percent increase in consumption from current levels of use and T is the time (in years) before the resources are depleted. If our consumption of coal increases by 14% per year, in how many years will we deplete our coal resources?

A) 88 years
B) 14 years
C) 29 years
D) 67 years
E) 39 years