Questions about Adobis' Zakum pre-quests.

1. Are the required quests yo get into the Zakum PQ, just the three missions Adobis gives you?
2. What do you have to do and how to finish these quests? (I checked Strategywiki and it only explained Mission 1)
^ in other words, can someone please explain how to finish each mission?
I might add more questions if i think of them...

Thanks in advance