Answer:
(1) For x = –12, g (x) = -9
For x = –9, g (x) = -3
For x = –6, g (x) = 3
For x = –3, g (x) = 9
(2) The principal amount of money is $80.
Step-by-step explanation:
(1)
The expression of g (x) is,

The complete table is:
x g (x)
-15 
-12 
-9 
-6 
-3 
0 
(2)
The formula for simple interest is:

Given:
I = $40
r = 10%
t = 5 years.
Compute the value of <em>P</em> as follows:



Thus, the principal amount of money is $80.

<h2>
Explanation:</h2>
As I understand, in this exercise, we have the following numbers:

By using calculator, let's convert those numbers into decimal form:

So arranging from least to greatest we have:

Put another way:

Given the equation p = 3(s + 100)/4
Where,
p = profit made
s = sales
Solving for s from the given equation
p = 3(s + 100)/4
Multiply both sides by 4
4p = 3(s + 100)
4p = 3s + 300
Subtract 300 from both sides of the equation
4p – 300 = 3s
Same as, 3s = 4p – 300
s = (4p – 300)/3
OR, s = 4p/3 – 100
If any of these two is in the options, it’s the right answer.