Answer: well to begin in mRNA if the letter T is in DNA and you need to make it of use it goes to an A in mRNA unless im not fully understanding the question this isn't done correctly.
Explanation: DNA: G-C, A-U there isnt any T in RNA or mRna but it would be
DNA:ACA . CAA . TGC
mRNA:UGU GUU . ACG
RNA:ACA . CAA . UGC