int tringPin = 7;
int echoPin = 6;
int relay = 5;

void setup() {
  Serial.begin(9600);
  pinMode(tringPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(relay, OUTPUT);
}

void loop() {
  Serial.begin(9600);
  long duration, distance;
  digitalWrite(tringPin, LOW);
  delayMicroseconds(2);
  digitalWrite(tringPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(tringPin, LOW);
  duration = pulseIn(echoPin, HIGH)
  distance = (duration/2) / 29.1;
    Serial.print(distance);
    Serial.println(" cm");
    delay(500)
    if (distance <= 65) {
      digitalWrite(relay, HIGH);
    } else {
      digitalWrite(relay, LOW);
    }
}