const int sensorPin=A0;
const float baselineTemp=20.0;
void setup() {
  Serial.begin(9600);
  for (int pinNumber=2; pinNumber<5;pinNumber++){
    pinMode(pinNumber, OUTPUT);
    digitalWrite(pinNumber, LOW);
  }
}
void loop() {
  int sensorVal=analogRead(sensorPin);
  Serial.print("Sensor Value: ");
  Serial.print(sensorVal);
  float voltage=(sensorVal/1024.0)*5.0;
  Serial.print(", volts: ");
  Serial.print(voltage);
  Serial.print(", degrees: ");
  float temperature = (voltage-.5)*100;
  Serial.print(temperature);
  Serial.print("\n")
  if(temperature<baselineTemp+2){
    digitalWrite(2, LOW);
    digitalWrite(3, LOW);
    digitalWrite(4, LOW);
  }
  else if (temperature >= baselineTemp+2 && temperature<baselineTemp+4){
    digitalWrite(2, HIGH);
    digitalWrite(3, LOW);
    digitalWrite(4, LOW);
  }
  else if (temperature >=baselineTemp+4&& temperature<baselineTemp+6){
    digitalWrite(2, HIGH);
    digitalWrite(3, HIGH);
    digitalWrite(4, LOW);
  }
  else if (temperature >=baselineTemp+6){
    digitalWrite(2, HIGH);
    digitalWrite(3, HIGH);
    digitalWrite(4, HIGH);
  }
  delay(250);
}