5x+7=54 how do you do this, im so confused. its 2 equations solving

What processes take place before the mature mrna exits the nucleus?

Which enzyme is responsible for “unzipping" the dna by breaking the hydrogen bonds between the nucleotides?

Mrna: gcuaauguc what amino acids does the mrna above code for? what type of amino acids or function are uag, uga, and uaa coding for? which codon (3 letters) signals translation to start and also codes for the amino acid methionine (met)?