A boat can move upstream at 35 kmph and downstream at 65 kmph, then the speed of the current is?  Choose the correct answer
A) 15 B) 8 C) 9 D) 12 E) 10
US = 35   DS = 65   M = (65- 35)/2= 
<gadget id="calculator">(65- 35)/2</gadget>
<output>15</output>
15   15nswer:15
<result>A</result>
A boat can move upstream at 35 kmph and downstream at 65 kmph, then the speed of the current is?