Please explain your answers, I am trying to prepare for a midterm. Thank you!

Consider the following loop lw $16, 0 ($4) lw $17, 4 ($4) add $20, $16, $17 sw $20, 0 ($4) addi $4, $4, 8 bne $4, $14, loop Loop: Unroll the loop 3 times (i.e., 4 old iterations become one new iteration) Assume that the number of iterations is divisible by 4. Optimize the code; reduce unnecessary arithmetic operations, and reschedule the instructions to minimize stalls in a 5-stage MIPS pipeline. (30 points) Consider the following loop lw $16, 0 ($4) lw $17, 4 ($4) add $20, $16, $17 sw $20, 0 ($4) addi $4, $4, 8 bne $4, $14, loop Loop: Unroll the loop 3 times (i.e., 4 old iterations become one new iteration) Assume that the number of iterations is divisible by 4. Optimize the code; reduce unnecessary arithmetic operations, and reschedule the instructions to minimize stalls in a 5-stage MIPS pipeline. (30 points)