The answer is 3’-tactttaggatc-5’. This is complementary to 5'-augaaauccuag-3' of the mRNA. It is important to note that RNA has no thiamine but instead has uracil (Thymine is a methylated form of Uracil.). The other principles on bae pairing apply where C pairs with G, and U with A. Thiamine is used in DNA because it gives it more stability than uracil does.