Answer:
16.7s
2x10^1 s (if you need a 1 significant digit answer)
Explanation:
The formula for average velocity is
Vavg = Δd/Δt
Fill in the known values
6m/s = 100m/Δt
Rearrange the equation
Δt = 100m/6m/s
Δt = 16.7s
note: this answer assumes that the person travels at a constant 6m/s (the person does not slow down or speed up)