The plant manager has a decision to make. She needs to reduce the concentration of salt in the 8000- gallon tank from 30000 mg/L to 1000 mg/L. she can do it in one of two ways.

a.     She can start flushing it out by keeping the tank well mixed while running in a hose with clean water (zero salt) at a flow rate of 60 gallons per minute (with an effluent of 60 gallons per minute, obviously).

b.     She can empty out some of the saline water and fill it up again with enough clean water to get 1000 mg/L. the maximum rate at which the tank will empty is 60 gallons per minute, and the maximum flow of clean water is 100 gallons per minute.

1.     If she intends to do this job at the shortest time possible, which alternative will she choose?

2.     Jeremy Rifkin points out that the most pervasive concept of modern times is efficiency. Everything has to be done so as to expand the least energy, effort, and especially time. He notes that we are losing our perspective on time, especially if we think of time in a digital way (as digital numbers on a watch) instead of in an analog way (hands on a conventional watch). With the digits we cannot see where we have been, and we cannot see where we have been, and we cannot see where we are going, and we all lose perspective of time. Why, indeed, would the plant manager want to empty out the tank in the shortest time? Why is she so hung up with time? Has the issue of having time (and not wasting it) become a pervasive value in our lives, sometimes overwhelming our other values. Write a one-page paper on how you value time in your life and how this value influences your other values.