Spawn random prefabs at multiple locations

Hello, I am trying to randomly generate a city. I have 20 points in the world and with one script I'd like to randomly generate a building from a list of 10 at each one of those points. I am stuck and don't know where to go with the code. I have a code but all it is able to do is randomly spawn a building at one location (the location which has this code) I need it to be able to randomly spawn a building (different buildings) at 20 different locations. Any assistance helps! Thank you! Code:

 //The list of the 20 spawn points
 public var Block : Transform [];
 
 public var ObjectSpawned : GameObject;
 
 //The list of the 10 buildings to randomly spawn at each spawn point
 public var ObjecttoSpawn1 : GameObject;
 public var ObjecttoSpawn2 : GameObject;
 public var ObjecttoSpawn3 : GameObject;
 public var ObjecttoSpawn4 : GameObject;
 public var ObjecttoSpawn5 : GameObject;
 public var ObjecttoSpawn6 : GameObject;
 public var ObjecttoSpawn7 : GameObject;
 public var ObjecttoSpawn8 : GameObject;
 public var ObjecttoSpawn9 : GameObject;
 public var ObjecttoSpawn10 : GameObject;
 
 var TimeToSpawn : int;
 var RandomNumber : int;
 RandomNumber = Random.Range(1.0, 5.0);
 TimeToSpawn = Random.Range(1.0,10.0);
 
 function Update () 
 {
 if(Input.GetKeyDown(KeyCode.Space)) 
 {
 Invoke ("spawnObject", TimeToSpawn); //Spawn an object after time and once space is pressed
 }
 }
 
 
 
 function Start () 
 {
 //These designate an object to a number when the random number is picked
 //I would like the random number to reshuffle so that there is a random chance for each building to be spawned at each spawn point
 if (RandomNumber == 1)
 {
     ObjectSpawned = ObjecttoSpawn1;
 }
 if (RandomNumber == 2)
 {
     ObjectSpawned = ObjecttoSpawn2;
 }
 if (RandomNumber == 3)
 {
     ObjectSpawned = ObjecttoSpawn3;
 }
 if (RandomNumber == 4)
 {
     ObjectSpawned = ObjecttoSpawn4;
 }
 if (RandomNumber == 5)
 {
     ObjectSpawned = ObjecttoSpawn5;
 }
 if (RandomNumber == 6)
 {
     ObjectSpawned = ObjecttoSpawn6;
 }
 if (RandomNumber == 7)
 {
     ObjectSpawned = ObjecttoSpawn7;
 }
 if (RandomNumber == 8)
 {
     ObjectSpawned = ObjecttoSpawn8;
 }
 if (RandomNumber == 9)
 {
     ObjectSpawned = ObjecttoSpawn9;
 }
 if (RandomNumber == 10)
 {
     ObjectSpawned = ObjecttoSpawn10;
 }
 }//Start Function end bracket
 
 function spawnObject()
 {
 //Spawn Object at curret location
 //I do not know how to code it so that it spawns 20 different times
 Instantiate (ObjectSpawned, transform.position, transform.rotation); 
 }