I have many problems in TvZ, most notably the lack of a good build order. I usually just get rolled by mutalisks, when they mass them. After about 20 mutas, they do so much splash damage not even marines can kill them.
I need a good build order for TvZ.
I also have a general problem in which I do not know how many barracks/factories/starports I can support with my economy. Is there a way to tell, such as X SCVs = 4 rax, 1 factory, etc.