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Question 3. (10 Points) Answer the following questions: a) Name an instruction that would be used to return to the main routine from the (non- exception handling) subroutine. Which register(s) will be updated after this execution? b) Why do we use MOVEQ or ADDO instead of MOVE or ADD instruction? (Explain with an example) c) An address register can hold up to 32 bits. Explain why the upper 8 bits of address register values will be always 0 in MC68000