 
 <translate> Speed downstream = 60 + 20 = 80 kmph
Speed upstream = 60 - 20 = 40 kmph
The answer: (B). <ibo> Ọsọ n'okpuru mmiri = 60 + 20 = 80 kmph Speed elu iyi = 60 - 20 = 40 kmph Azịza ya bụ: (B). 