LED Blink

Solving Approach

How do you plan to solve it?

 I just recreate the wiring in wokwi.com and simulate. Then in order to get the 10mA I used a 500 ohms resistor since the Arduino Uno outputs 5V so 5V divided by 500 ohms equals 10mA curren according to Ohms Law.
 

Code

void setup() {
 pinMode(13, OUTPUT);

}

void loop() {
  digitalWrite(13, HIGH);
  delay(400);
  digitalWrite(13, LOW);
  delay(800);
}

Output

Video

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Photo of Output

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