Probably a pie (or circle) graph.
No.
a whole number
It is misleading to use the mean as a descriptor of a data set when the median or mode would be more representative of the data set as a whole.
The mean tells the sum of the whole set of data.h
Because you can see how each data item compares to the whole data set. A larger percent would show a larger slice of pie. It will be immediately clear that 50% is half of the pie.
Fraction
Pie chart. The entire "pie" shows the whole data set, while each "slice" shows each group of data.circle graphs
The median.
A fraction.
as a set {}
Pie or sector graph