Which answer explains the type of sequence 3, 9, 15,21 answers: geometric neither arthmetic

This is an arithmetic sequence because a geometric sequence is written out as
a,ar,ar^2,ar^3 and so on.

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.