A boatman goes 2 km against the current of the stream in 1 hour and goes 1 km along the current in 12 minutes. How long will it take to go 5 km in stationary water? Options:
A) 40 minutes
B) 1 hour
C) 1 hour 25 min
D) 1 hour 30 min
E) 1 hour 10 min
speed (upstream) =2/1= 
<gadget id="calculator">2/1</gadget>
<output>2</output>
2 kmhr   speed (downstream)=1/(12/60)= 
<gadget id="calculator">1/(12/60)</gadget>
<output>5</output>
5 kmhr   speed in still water= 1/2 (2+5) = 3.5 kmhr   time taken in stationary = 5/3.5 = 1 hrs 25 min   ANSWER:1 hour 25 min
<result>C</result>
A boatman goes 2 km against the current of the stream in 1 hour and goes 1 km along the current in 12 minutes. How long will it take to go 5 km in stationary water?