-8 and -9 because it is negative

The answer is above.
Additional note 1:

Additional note 2:
In the answer I filled in "0" at the place where "n" was. This is because the question tells us n=0
Answer:
<h2>The fourth graph, from left to right, is the correct answer.</h2>
Step-by-step explanation:
The given piecewise function is

Notice that the domain of the function specifies that, from zero to three, the function represents a decreasing (because the variable is negative) straight line. When the function is defined from 3 to infinite, the function is a constant of 5.
<em>So, the right graph must shows first a decreasing line, where the initial point is solid and the final point is empty, as the fourth fraph (from left to right), then it must show a horizontal line with an initial point solid.</em>
<em />
Therefore, the fourth graph, from left to right, is the correct answer.
Answer:
The volume of the solution with 20% acid is 27 gallons and the one with 10% acid is 18 gallons
Step-by-step explanation:
Myra needs to mix "x" gallons of the solution with 20% and "y" gallons of the solution with 10%. The volume of the final solution must be 45 gallons, therefore:
x + y = 45
The concentration of acid of the final solution is:
0.2*x + 0.1*y = 45*0.16
0.2*x + 0.1*y = 7.2
Therefore we have a system of equation:
x + y = 45
0.2*x + 0.1*y = 7.2
We need to multiply the first equation by -0.1:
-0.1*x -0.1*y = -4.5
0.2*x + 0.1*y = 7.2
We now sum both equation:
0.1*x = 2.7
x = 2.7/0.1 = 27 gallons
y = 45 - 27 = 18 gallons