# A goa can travel at a speed of 8 kmh−1 in still water on a lake. In the flowing water of a stream, it can move at 8kmh −1 relative to the water in the stream. If the stream speed is 3kmh −1 , how fast can the boat move past a tree on the shore in travelling (i) upstream (ii) downstream?

Question : A goa can travel at a speed of 8 kmh−1 in still water on a lake. In the flowing water of a stream, it can move at 8kmh −1 relative to the water in the stream. If the stream speed is 3kmh −1 , how fast can the boat move past a tree on the shore in travelling (i) upstream (ii) downstream?

(A) $5kmh^{-1}and 11kmh^{-1}$

(B) $11kmh^{-1}and 5kmh^{-1}$

(C) $8kmh^{-1}and 8kmh^{-1}$

(D) $5kmh^{-1}and 5kmh^{-1}$