A Tank Contains 2000 L of a Solution Consisting of 50

question 94

Multiple Choice

A tank contains 2000 L of a solution consisting of 50 kg of salt dissolved in water. Pure water is pumped into the tank at the rate of 10L/s, and the mixture (kept uniform by stirring) is pumped out at the same rate. How long will it be until only 5 kg of salt remain in the tank?

• A) approximately 689 seconds
• B) approximately 703 seconds
• C) approximately 460 seconds
• D) approximately 276 seconds

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Definitions:

Stage 1 Sleep

The initial phase of the sleep cycle, a light sleep stage from which individuals can be easily awakened.

REM Sleep

A stage of sleep characterized by rapid eye movement, vivid dreaming, and increased brain activity.

Dement's Experiment

A study by William Dement, focusing on the phases and effects of sleep, particularly REM sleep, on emotional health and memory, significantly contributing to sleep research.

Memory

The faculty by which the brain encodes, stores, and retrieves information.