1) The following frequency distribution shows the length (in feet) of the main spans of the longest suspension bridges in the United States. Construct a frequency polygon.

Class boundaries	Frequency
1260-1734	12
1735-2209	6
2210-2684	3
2685-3159	1
3160-3634	1
3635-4109	1
4110-4584	2

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2) One of the air pollutants that is measured in selected cities is sulfur dioxide. This pollutant occurs when fossil fuels are burned. This pollutant is measured in micrograms per cubic meter (μg/m3).  The results obtained from a sample of 24 cities are shown in the following frequency table. Construct a frequency polygon from this data.

Class Boundaries	Frequency
10-14	6
15-19	4
20-24	3
25-29	2
30-34	5
35-39	1
40-44	2
45-49	1

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3) The frequency distributions shown indicate the percentages of public school students in fourth-grade mathematics who performed at or above the required proficiency levels for the 50 states in the United States. Create a frequency polygon for the following data.

Class Boundaries	Frequency
17.5-22.5	5
22.5-27.5	9
27.5-32.5	11
32.5-37.5	16
37.5-42.5	8
42.5-47.5	1