Nonrestrictive because the sentence you "My brother who lives in Hawaii is a surfer" is not restrictive but the answer to your question is = Nonrestrictive.
An example of a typo would be spelling a word incorrectly. Let's say I were to spell whgat. The correct spelling would be What.
Answer:
Dear Teacher(her/his name)
Explanation:
Your have always helped me when I needed it.
Whenever I had questions you had answers.
Whenever I had doubts you gave reassurance.
I think your a awesome teacher and hope you have fun teaching.
