Answer from cs61c-cd (Charles Leung 15905350) for Question 1
No, if they have the same bit pattern, then all the instructions would be the same.  ex: the op, rs, rt... values would all be the same.  Then the machine code would mean the exact same thing. Since the op and funct fields represent the fuction being used in R and I type machine codes, then the MIPS instructions cannot be diferent if the bit pattern is the same.