The speed of a boat in still water is $$5\frac{1}{3}$$ km/h. It is found that the boat takes thrice as much time to row up than it does to row down the same distance in the river su·eam. Find the speed of the river stream.

A

$$\frac{23}{27}$$ m/sec

B

$$\frac{22}{27}$$ m/sec

C

$$\frac{20}{27}$$ m/sec

D

$$\frac{19}{27}$$ m/sec