Question: 1. Current stocks of mineral M are 250 million tonnes. If these stocks are continually being used up at an annual rate of 9%, what amount of M will remain after 30 years?
2. A renewable natural resource R will allow an estimated maximum consumption rate of 200 million units per annum. Current annual usage is 65 million units. If the annual level of usage grows continually at an annual rate of 7.5% will there be sufficient R to satisfy annual demand after
(a) 5 years,
(b) 10 years,
(c) 15 years,
(d) 20 years?