int temperature=120;
void setup() {
  // put your setup code here, to run once:
  pinMode(7, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(8, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(temperature < 50 && temperature > 10)
  {
    digitalWrite(6, HIGH);
    delay(500);
    digitalWrite(6, LOW);
    delay(500);
  }
  else if(temperature < 100 && temperature > 51)
  {
    digitalWrite(7, HIGH);
    delay(500);
    digitalWrite(7, LOW);
    delay(500);
  }
  else
  {
    digitalWrite(8, HIGH);
    delay(500);
    digitalWrite(8, LOW);
    delay(500);
  }
}