Which of the following codons acts as a stop signal?

The cell-free system was helpful in which of the following?

The code of $mRNA$ and proteins are:

Who proposed that the genetic code for amino acids should be made up of three nucleotides?

The arrangement of three bases in the genetic code signifies a specific

For the genetic code,choose the correct option for the given statements. Where $T$ stands for True and $F$ stands for False.
$(1)$ Phenylalanine $(Phe)$ amino acid is coded by more than three codons.
$(2)$ The codon is read in $t-RNA$ in a contiguous fashion.
$(3)$ $UUC$ would code for phenylalanine.
$(4)$ $AUG$ codes for Methionine.