1. He is a good actor as much as he is a good singer. (Is this sentence correct?)
2. He is as much good in acting as he is in singing. (Is this sentence correct as well, though It may differ from the first one in meaning?)
3. He is as good in acting as he is in singing (Actually I cannot decide whether 2 is correct or 3 is).
4. As he is a good actor, so he is a good singer. (Is this correct and similar to the any sentence from 1,2 and 3?)