What is the difference between Data Hazard and Dependencies in Pipelining

In my GATE Exam I have given with the following question statements and

1. R5 ← R0 + R1
2. R6 ← R2 * R5
3. R5 ← R3 - R6
4. R6 ← R5/R4
5. X ← R6

the question was to calculate number of Output,True and Anti Dependencies in the instructions.

I calculated and it turns out to be

RAW (True Dependency)

• I1 - I2 (R5)
• I2 - I3 (R6)
• I3 - I4 (R5)
• I4 - I5 (R6)

WAR (Anti-Dependency)

• I2 - I3 (R5)
• I3 - I4 (R6)

WAW (Output Dependency)

• I1 - I3 (R5)
• I2 - I4 (R6)

Now my friend argued

Had the question been to calculate the number of possible data hazards the answer would have been different because Dependencies and hazards are not same

When we calculate possible hazards we should reorder the instructions and find the dependencies . Dependencies and hazards are closely related but not same . He has also gave me a pdf .which implies that a dependency may not be a hazard.A dependency is a "possible hazard" considering all cases which involve reordering of instructions etc.But the solution of gate question is involving those dependencies only which are causing hazards only not potential or possible hazard.

I go threw them but was not able to finalize proper relationship between hazard and dependencies . Can someone of you could better explain me how are Dependencies ,Possible Hazards and Potential Hazards Relate to each other ? ( Explanation using the above instruction set is preferred )