Final answer:
The question seems to pertain to driving safety regulations, not Physics; the correct placement distances for warning devices can vary and are dependent on local traffic laws.
Step-by-step explanation:
When placing warning devices like flares, lamps, lanterns, or portable reflectors around a broken-down vehicle, the correct distance from the front and rear of the vehicle will depend on local laws and the specific situation on the road. However, the question appears to be from a driving safety or rules of the road context rather than physics. Without specific regional guidelines provided within the question, it's not possible to answer this accurately. Typically, there are standard distances either recommended or mandated by local traffic laws, and it's vital to refer to these regulations for the correct answer.