How do you script to show random image for seconds?

To the point, i hope there’s good people outside. Just say i have 5 or 10 pictures and i want it show randomly in random time for 1 second? How do you do that?

using UnityEngine.UI;

public float time_min = 1f;
public float time_max = 3f;
public Sprite[] sprites = new Sprite[0];
public Image image;

void Start() {

public IEnumerator ShowRandomImage() {
     while(true) {
          image.sprite = sprites[Random.Range(0, sprites .Length)];
          image.enabled = true;
          yield return new WaitForSeconds(1);
         image.enabled = false;
          yield return new WaitForSeconds(Random.Range(time_min, time_max));

// you must drag and drop images into all the blanks in the inspector!!!

	public Texture2D pic0;
	public Texture2D pic1;
	public Texture2D pic2;
	public Texture2D pic3;
	public Texture2D pic4;
        public int pick;

	Texture2D[] pics;
	int i;
	float timer;

	void Start () {

		//pack images into an array to make things easy
		pics = new Texture2D[5];

		pics [0] = pic0;
		pics [1] = pic1;
		pics [2] = pic2;
		pics [3] = pic3;
		pics [4] = pic4;


	void Update () {

		timer -= Time.deltaTime;
		if (timer < 0) {timer = 2.5f;//<--this happens about every second;

			    //get a random number not equal to current

	void OnGUI(){
		//display our image
		GUI.DrawTexture (new Rect (50, 50, 300, 300), pics [pick]);