(20 points) Complete the code below to create a user defined function called circleArea, that takes one float as argument and returns the area of a circle of radius r. As shown in the code below, the result is then saved in the variable area and printed on the serial monitor. 2. void setup ) float area,r; Serial.begin (9600) r 10.0; area = circleArea (r) ; Serial.println (area); void loop)) 11 1oop) is intentionally empty float circleArea ( cnal.lint In else