Needs help: deals with area and circumference

Area of the big circle-area of the small circle is what you are looking for so
Big circle is (3.5)^2pi=12.25pi
Small circle is 4pi
12.25pi-4pi=8.25pi
8.25pi=26
26cm^2

The major difference is that a histogram is only used to plot the frequency of score occurrences in a continuous data set that has been divided into classes, called bins.  bar charts, on the other hand, can be used for a great deal of other types ofvariables  including  ordinal  andnominal  data sets.