QUESTION 15 Given the following code segment. public class ColorWheel { public static int color; private int brightness; public ColorWheel () { setBrightness(6): } public ColorWheel (int c) { brightness = c } public ColorWheel (double d) { brightness = (int)d; } public ColorWheel (int c, int z) { int bri = 7; brightness = c+z: setBrightness(bri); } public void setBrightness(int bright) {brightness = bright; } public String toStringo { return "The bright is " + brightness; } } public void setBrightness(int bright) {brightness = bright; } public String toStringo { return "The bright is " + brightness: } public class ColorApp{ public static void main(String args) { ColorWheel C1 = new ColorWheel(); ColorWheel C2 = new ColorWheel(2); ColorWheel 3 = new ColorWheel(4.5); ColorWheel C4 = new ColorWheel(2,3); System.out.print(c4); C4.setBrightness(3); } } How many instance Variables does the code have? 02 3 no instance variable