Answer:
Both slug and snail traveled with the same speed.
Step-by-step explanation:
Given,
Distance covered by slug = 3 cm,
Time taken = 3 seconds,

So, the speed of the slug = 
= 1 cm per sec,
Now, distance covered by snail = 6,
Time taken = 6 seconds,
So, the speed of the snail = 
= 1 cm per seconds,
Hence, both slug and snail traveled with the same speed.