Last one.....car travels 9 meters and then travels 9 meters in opposite direction
Step-by-step explanation:
6a.


6b.



Answer:
9 mph
Step-by-step explanation:
-let x be the speed of current and t be time. The speed equation for both directions can then be represented as:

#Since t is equal in both, we can do away with t.
#We the divide the downstream equation by the upstream equation as:

Hence, the boat's speed in still water is 9 mph