A man can row his boat with the stream at 6 km/h and against the stream in 4 km/h. The man's rate is?  Choose the correct choice from the following answers.
A) 5 kmph
B) 1kmph
C) 7 kmph
D) 9 kmph
E) 11 kmph
Explanation:   DS = 6   US = 4   S = ?   S = (6 - 4)/2= 
<gadget id="calculator">(6 - 4)/2</gadget>
<output>1</output>
1 kmph   Answer: 1kmph
<result>B</result>
A man can row his boat with the stream at 6 km/h and against the stream in 4 km/h. The man's rate is?