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.
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.
The mean tells the sum of the whole set of data.h
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 {}
yes* * * * *No. If you have a small, even number of observations, the median is the average of the two middle values. This will usually NOT be part of the data set.