LOOP UNROLLING / Data Hazards

Question #1
What is the 2 times loop unrolling of the following?

Loop: ADD R0, R0 R2
SUBI R1, R1, #1
BNEZ R1, Loop

Question # 2

What type of hazards exist in this code?

LW R1, 0(R2)
ADDI R1, R1, #1

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