Create a JavaFX program in java that does the following
items:
Display a drawing area of dimension 500 x 400, with a black
background.
Provides a radio button group to allow the user to select one
of the following three colors: red, green, and blue. Upon startup,
the red radio button should be selected.
Each time the user clicks in the drawing area, a circle of size
10 of the color selected by the radio button group in item 2...