void setup() {
  // put your setup code here, to run once:
pinMode(25, OUTPUT); 
pinMode(26, OUTPUT);
pinMode(27, OUTPUT);
}

void loop() {
 digitalWrite(25, HIGH);
 digitalWrite(26, LOW);
 digitalWrite(27, LOW);// put your main code here, to run repeatedly:
 delay(3000);

 digitalWrite(25, LOW);
 digitalWrite(26, HIGH);
 digitalWrite(27, LOW);// put your main code here, to run repeatedly:
 delay(1000);
 
 digitalWrite(25, LOW);
 digitalWrite(26, LOW);
 digitalWrite(27, HIGH);// put your main code here, to run repeatedly:
 delay(4000); // this speeds up the simulation
}