a researcher identifies the the nucleotide sequence AAC in a long strand of RNA inside a nucleus. in the genetic code, AAC codes for the amino acid asparagine. When that RNA becomes involved in protein synthesis, will asparagine necessarily appear in the protein?

The answer is no, it does not necessary means that asparagine will appear in the synthesized protein.

This is because transcribed RNA (pre-RNA) must be processed into a messenger RNA (mRNA) before it enters the translation (protein synthesis). Processing of the RNA includes steps of adding a 5' cap and a 3' poly-A tail to the end. Also, some sections of the RNA transcript (introns) are cut, and the remaining sections (exons) are stuck back together, so the nucleotide sequence AAC might be cut.