4. what is the difference between an intron and an exon?

xons are coding areas whereas introns are non-coding areas. ... An exon is termed as a nucleic acid sequence which is represented in the RNA molecule. Introns, on the other hand, are termed as nucleotide sequences seen within the genes which are removed through RNA splicing for generating a mature RNA molecule

this is true, assuming that the allele is completely recessive and incomplete dominance is not a factor.