Answer: Second option is correct.
Step-by-step explanation:
Since we have given that
Speed of Milla = 5 km per hour
Speed of Luka = 4 km per hour
Distance between Milla and Luka = 3 km
Let the time be 't'.
As we know that
[tex]Distance=Speed\times time[/tex]
So, it becomes,
Distance covered by Milla + Distance covered by Luka = Total distance
[tex]5t+4t=3[/tex]
Hence, Second option is correct.