void setup() {
  // put your setup code here, to run once:
pinMode (4,OUTPUT);
pinMode (5,OUTPUT);
pinMode (6,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite (4,HIGH);tone (6,300,100);
delay (500);
digitalWrite (4,LOW);
delay (500);
digitalWrite (5,HIGH);
delay (500);
digitalWrite (5,LOW);
delay (500);
}