A Tank Contains 200 Gallons of Water in Which 300 $A ( t )$

question 6

Multiple Choice

A tank contains 200 gallons of water in which 300 grams of salt is dissolved. A brine solution containing 0.4 kilograms of salt per gallon of water is pumped into the tank at the rate of 5 liters per minute, and the well-stirred mixture is pumped out at the same rate. Let $A ( t )$ represent the amount of salt in the tank at time t. The correct initial value problem for $A ( t )$ is

• A) \(\frac { d A } { d t } = 2 + A / 40 , A ( 0 ) = 0.3\)
• B) \(\frac { d A } { d t } = 2 - A / 40 , A ( 0 ) = 0.3\)
• C) \(\frac { d A } { d t } = 5 + A / 40 , A ( 0 ) = 300\)
• D) \(\frac { d A } { d t } = 5 - A / 40 , A ( 0 ) = 300\)
• E) \(\frac { d A } { d t } = 0.4 - A / 40 , A ( 0 ) = 300\)

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Definitions:

Genetic Mapping

Identifying the exact position and chemical structure of particular genes within a chromosome.

Polygenic Study

Research aimed at understanding traits or conditions that are influenced by multiple genes, in contrast to those determined by a single gene.

Survival Problem

A situation or scenario where an individual or group must overcome obstacles to remain alive, often used in psychology to study decision-making.

Genetic Mutation

A permanent alteration in the DNA sequence that makes up a gene, which can result in a change in the physical traits or health of an organism.