Distance magic

const int echo = 13;
const int trig = 12;
const int LED1 =8;
const int LED2 =7;
const int LED3 =6;
const int LED4 =5;
const int LED5 =4;
int duration = 0;
int distance = 0;
void setup()
{
 pinMode(trig,OUTPUT);
 pinMode(echo,INPUT);
 pinMode(LED1,OUTPUT);
 pinMode(LED2,OUTPUT);
 pinMode(LED3,OUTPUT);
 pinMode(LED4,OUTPUT);
 pinMode(LED5,OUTPUT);
 Serial.begin(9600);
}
void loop()
{
 digitalWrite(trig,HIGH);
 delayMicroseconds(1000);
 digitalWrite(trig,LOW);
 duration = pulseIn(echo,HIGH);
 distance = (duration/2)/28.5;
 Serial.begin(distance);
if(distance <=7)
 {
   digitalWrite(LED1,HIGH);
 }
 else
 {
   digitalWrite(LED1,LOW);
 }
 if(distance <=7)
 {
   digitalWrite(LED1,HIGH);
 }
 else
 {
   digitalWrite(LED1,LOW);
 }
if(distance <=14)
 {
   digitalWrite(LED2,HIGH);
 }
 else
 {
   digitalWrite(LED2,LOW);
 }
if(distance <=21)
 {
   digitalWrite(LED3,HIGH);
 }
 else
 {
   digitalWrite(LED3,LOW);
 }
if(distance <=28)
 {
   digitalWrite(LED4,HIGH);
 }
 else
 {
   digitalWrite(LED4,LOW);
 }
if(distance <=35)
 {
   digitalWrite(LED5,HIGH);
 }
 else
 {
   digitalWrite(LED5,LOW);
 }
}