Histogram And Frequency Polygon

"Please indicate if the following statements are true or false.
1.The cumulative frequency is the sum of the frequencies accumulated to the upper boundary of a class in the distribution.
2.A frequency polygon and a histogram have the same overall shape.
3.A histogram is a graph that represents the cumulative frequencies for the classes in a frequency distribution. 
4.A stem and leaf plot is useful for keeping more precision than a grouped frequency distribution.
5.A time series graph represents data that occur over a specific period.
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