Final answer:
The sentence should be punctuated as: Whether I like it or not, by tomorrow, I must choose a college to attend. The relative clauses are non-essential and provide additional information.
Step-by-step explanation:
The correct punctuation for the sentence is: Whether I like it or not, by tomorrow, I must choose a college to attend. The clause "whether I like it or not" is non-essential, and it adds extra information to the main part of the sentence. The clause "by tomorrow" is also non-essential and provides additional information about the timing of the action.
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