//exercise 2:Change the program to blink on and off 5 times then stop for 3 seconds. Each blink should be 0.5s
int led1 = D2;

void setup() {

    pinMode( led1, OUTPUT);
}

void loop() {
    for (int i = 0; i < 5; i++){
        digitalWrite( led1, HIGH );
        delay( 500 );
        digitalWrite( led1, LOW );
        delay( 500 );
       }
    digitalWrite( led1, LOW );
    delay( 3000 );

}