I believe it's 3 months because 12 divided by 4 is 3.
If we just have

that's an amplitude of 1 and a period of 
Let's modify this step by step.
Amplitude of 4. Four times the amplitude means a factor of 4 on the outside.

Period of π. Double the period means a factor of 2 on the inside.

Horizontal shift of π/2 to the left. To the left means adding a positive number to x. The question appear ambiguous. It's not clear to me if we add to x or 2x; let's make it

Vertical shift of 3:


Depending on the interpretation of the phase shift, that pi may be a pi/2.
Answer: 
Answer:
15 < x < 31
Step-by-step explanation:
Given 2 sides of a triangle then the third side x is in the range
difference of 2 sides < x < sum of 2 sides , that is
23 - 8 < x < 23 + 8
15 < x < 31
Answer:
Step-by-step explanation:
I attached the work and answer below, take a look!
Answer: Choice C
scale starts at $5 and goes to $40 with a regular $5 interval
even though we don't start at 0, the difference in bar heights is not exaggerated
graph is not misleading
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Explanation:
Choice A is not true because the vertical axis starts at 5 and not 0
Choice B is the same story as choice A.
Choice D is not true because the vertical axis does not use an irregular interval. The interval or tickmark distance is $5 each time. In other words, the value goes up by 5 each time.
So far, choices A, B and D have been crossed off the list. The only thing left is choice C.
Despite the fact that the vertical axis starts at 5, instead of 0, the graph is not misleading. The heights of the bars can be compared to see that brand H is the most expensive brand. So in a sense, we can ignore the data values along the vertical axis and still be able to see that brand H is the most expensive. The other brands are close to one another in cost.
side note: the bar graph should have a zig-zag line at the very bottom of the vertical axis to indicate "we are not starting at y = 0". This is handy if you happen to start with much larger y values.