### A good answer might be:

           0 1 0 1 0  0 1 0 0 1  1 0 1 0  1 1 1 1  1 1 1 1  0 0 0 0
    001101 _ _ _ _ _  _ _ _ _ _  _ _ _ _  _ _ _ _  _ _ _ _  _ _ _ _

    ori     $10          $9         a         f        f        0

           operand      dest           immediate operand
           reg.         reg.

# Machine Instructions Compared

Here again is the `ori` machine instruction:

       3    4    0    8    0    f    a    5     -- machine instruction in hex

    001101  00000 01000 0000 1111 1010 0101    -- fields of the instructuion

    opcode  oper  dest  immediate operand      -- meaning of the fields
            -and  reg.
            reg.

    ori     $0      $8     0    f    a    5

The layout of this machine instruction is different from the `addu` instruction we looked at in chapter 10:

       0    1    0    9    5    0    2    1    -- machine instruction in hex

    000000 01000 01001 01010 00000 100001      -- fields of the instruction

    opcode oprnd oprnd dest  ----- 2ndary      -- meaning of the fields

    ALUop   $8    $9   $10           addu

Both instructions are 32 bits wide (as are all MIPS R2000/R3000 instructions). The first six bits are the opcode, which calls for an ALU operation. The `addu` instruction further specifies the operation in the last six bits, the secondary opcode. The `addu` instruction does not have an immediate operand.

### QUESTION 9:

Do the fields of two different machine instructions necessarily have the same size and same meaning?