Zombie wave spawn help?

Hello, im a novice at coding, and am needing a little help with waves of zombies spawning in my scene. So i have multiple spawn points in my scene and i want on wave 1 for example to spawn 5 zombies, but i want them to spawn at the spawn points randomly, maybe 2 spawning at one point and 1 at another ect.... And i have an audio sound that i would like to play when the wave is complete. Below are some of my variables, if anyone can help it would be much appreciated.

 var zombiePrefab : GameObject;
 var zombiesSpawned : int;
 var spawnPointOne : GameObject;
 var spawnPointTwo : GameObject;
 var spawnPointThree : GameObject;
 var spawnPointFour : GameObject;
 var spawnPointFive : GameObject;
 var spawnPointSix : GameObject;
 var spawnPointSeven : GameObject;
 var spawnPointEight : GameObject;
 var spawnPointNine : GameObject;
 var spawnPointTen : GameObject;