A man swims downstream 28 km and upstream 12 km taking 2 hours each time, what is the speed of the man in still water?  Pick one.
A) 10
B) 8
C) 5
D) 2
E) 4
28 --- 2 DS = 14   ? ---- 1   12 ---- 2 US = 6   ? ---- 1 M = ?   M = (14 + 6)/2= 
<gadget id="calculator">(14 + 6)/2</gadget>
<output>10</output>
10   10nswer:10
<result>A</result>
A man swims downstream 28 km and upstream 12 km taking 2 hours each time, what is the speed of the man in still water?