Mutation Problem

I have a trouble getting the answer to this question.

There are two parts to it. I answered the first one but I can't get the second part.

If the 3rd DNA base in your gene for insulin was mistakenly duplicated -- meaning another copy of that letter were placed between the current 3rd and 4th base --what type of mutation would that be?

Ok. That was the first part. I put "frameshift mutation" because it changes the codon of the DNA. How it is going to be readed changes because of the copy placed.

Using the first question, here is a question that I DID NOT get:

If the event above actually occurred, what would be the first three amino acids in the protein?

I have no clue how to do this. The insulin that I made was like this:

I don't have a codon of DNA. But I have RNA codon.

It was, at least first 9 letters were: GGGAUAGUG

When this is read to code for the protein, it became: CCCTATCAC

But how does this help me answering my question??

Please give good help, thank you!!!