Question

given the sequence of DNA nucleotide bases TTA GCC TTG give the complementary strand of mRNA produced during transcription

Answer 1

UUA GCC UUG would be the mRNA strand, when you change them from DNA to the DNA template strand it is the opposite so, AAT CGG AAC then you go opposite again but instead of T it's U.

Answer 2

The complementary mRNA strand would be AAU-CGG-AAC

Adenine (A) always matches with thymine (T) in DNA, and uracil (U) in RNA.
Guanine (G) always matches with cytosine (C) in both DNA and RNA.