1. The two strands spontaneously re-anneal. Once the transcription complex has moved on and the mRNA has started to peel off, the two DNA strands are free to re-form the same H-bonds that were disrupted by the RNA polymerase complex. This is not very different than renaturing two strands that were separated by heat-denaturation, only easier because the strands are still partially annealed to one another.
2 Lyzosomease? You mean lysozyme? The exact sequence will depend on the source. But whatever the source, it will be the same as coding strand of the DNA reading from 5’ to 3’ with any Ts (thymidines) replaced with Us (uracils). (The sugar will be ribose, now, instead of deoxyribose, but that doesn’t have anything to do with the sequence per se.)
I may be using incorrect terms, or at least terms that a purist wouldn’t approve (I’m not a purist)–the mRNA will be a copy of the "sense" strand of DNA, which is what I mean by coding strand. RNA polymerase uses the antisense strand as a template to make an RNA copy of the sense strand of the duplex.