A basic problem in system science is trying to quantify thelength of time a finite resource will last. This is an importantvalue because systems will often stop functioning if an importantresource becomes limited. Several important limiting resources havebeen suggested in the environmnetal literature as a potentialthreat to the continued existence of human society including food,water, soild, and petroleum (or other energy source).

A. In 1980, Petroleum was being consumed at the rate of 1.35 x1020 J yr-1. Estimated reserves are 1.0 x1022 J (Joules, a unit of energy). Given the 1980 Globalconsumption of oil, how long will the resource last?

B.What are the major assumptions inherent in this calculation if you were to use this number to predict the effects of the lossof petroleum as an energy resource for human society?

C. How will the major type of energy resource used by humansociety for its energy needs changed over the last 500 years?