Spawn delay time AT inspector...

Hello,

I have that SpawnScrip,

    using System.Collections;
     using UnityEngine;
     using System.Collections;
     using System.Collections.Generic;
     public class SpawnController : MonoBehaviour {
     
         public float maxWidth;
         public float minWidth;
     
         public float rateSpawn;
         private float currentRateSpawn;
     
         public GameObject tubePrefab;
     
         public int maxSpawnTubes;
     
         public List<GameObject> tubes;
     
         // Use this for initialization
         void Start () {
     
             for (int i = 0; i < maxSpawnTubes; i++) {
                 GameObject tempTube = Instantiate (tubePrefab) as GameObject;
                 tubes.Add (tempTube);
                 tempTube.SetActive (false);
     
             }
     
             currentRateSpawn = rateSpawn;
     
         }
     
         // Update is called once per frame
         void Update () {
     
             currentRateSpawn += Time.deltaTime;
             if (currentRateSpawn > rateSpawn) {
                 currentRateSpawn = 0;
                 Spawn ();
             }
         }
     
         private void Spawn() {
     
             float randWitdh = Random.Range(minWidth, maxWidth);
             GameObject tempTube = null;
     
             for (int i = 0; i < maxSpawnTubes; i++) {
                 if (tubes [i].activeSelf == false) {
                     tempTube = tubes [i];
                     break;
                 }
             }
     
             if (tempTube != null)
                 tempTube.transform.position = new Vector3 (randWitdh, transform.position.y, transform.position.z);
             tempTube.SetActive (true);
         }
     }

I want to create a function within the SPAWN, so I can put the minimum and maximum delay time that an object can be created by the inspector.

=]