2011 because it has the higher gpa of all of them
Answer:

Step-by-step explanation:











Let
= amount of salt (in pounds) in the tank at time
(in minutes). Then
.
Salt flows in at a rate

and flows out at a rate

where 4 quarts = 1 gallon so 13 quarts = 3.25 gallon.
Then the net rate of salt flow is given by the differential equation

which I'll solve with the integrating factor method.



Integrate both sides. By the fundamental theorem of calculus,





After 1 hour = 60 minutes, the tank will contain

pounds of salt.
Answer:
Evaluate:
-
- 
Factor:

Step-by-step explanation:
The rate charged per hour by each mechanic was: x = 75 $ / hr and y = 115 $ / hr.
<h3>What is a system of equations?</h3>
A system of equations is two or more equations that can be solved to get a unique solution. the power of the equation must be in one degree.
Given;
The first mechanic worked for 20 hours, and the second mechanic worked for 15 hours.
Together they charged a total of $3225.
For this case we have the following variables:
x be the amount of $ / hr that the mechanic obtains 1.
y be the amount of $ / hr obtained by mechanic 2.
An equation to express this would be:
x + y = 190
20x + 15y = 3225
Solving the system of equations we have:
20x + 15(190 -x) = 3225
20x + 2850 - 15x = 3225
5x = 375
x = 75
simililary
y = 190 - x
y = 115
Hence, the rate charged per hour by each mechanic was:
x = 75 $ / hr
y = 115 $ / hr
Learn more about equations here;
brainly.com/question/10413253
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