Depletion time is the time it takes to use up approximately _____% of the mineral reserves at a given rate of use.

Depletion time is the time it takes to use up approximately _____% of the mineral reserves at a given rate of use.

Depletion time is the time it takes to use up approximately _____% of the mineral reserves at a given rate of use.




a. 30

b. 50

c. 60

d. 70

e. 80







Answer: E