In circle r, line rd is a radius and line df is a tangent segment. which statement must be true? a.△rdf is a right triangle. b. rd=df c. rd=rf d.△rdf is an obtuse triangle.

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.

Aand b are correctly balanced reactions. they have the same number of atoms in both sides of the reaction