<h3>
Answer:</h3>
see attached for a graph
domain and range: all real numbers
<h3>
Step-by-step explanation:</h3>
The function is written in slope-intercept form, showing that it has a slope of -3 and a y-intercept of +7. The y-intercept (0, 7) is a point on the line, as is a point 1 unit to the right and down 3 units, (1, 4).
The graph will be the line through these two points.
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As with any odd-degree polynomial function, both domain and range are all real numbers: (-∞, ∞).
<h3>The minimum amount of sales Michael must have to earn at least $2500 in a month is $ 32000</h3>
<em><u>Solution:</u></em>
<em><u>The expression to Michael earnings is:</u></em>

Where,
b is the base salary, which is $ 900 in this sum
c is the commission rate
Given that commission rate is 5%
s is the sales
Michael must have to earn at least $2500 in a month
Here, at least means, "greater than or equal to" 2500
The inequality is framed as:
base salary + 5 % on sales
2500

Solve the inequality

Thus, minimum amount of sales Michael must have to earn at least $2500 in a month is $ 32000
a. The standard error is equal to the standard deviation divided by the square root of the sample size:
SE = (23 ppm)/√18 ≈ 5.42 ppm
b. The t statistic is given by the difference between the true and sample means, divided by the standard error:
t = (192 ppm - 180 ppm)/SE ≈ 2.21
c. The p-value is approximately 0.0204.
d. Since p < 0.05, the difference is significantly different, so we reject the null hypothesis.
e. A type I error might have occurred, since it's possible that the null hypothesis was true, but we ended up rejecting it.