A man swims downstream 72 km and upstream 45 km taking 5 hours each time; what is the speed of the current?  Choose one:
A) 1.7
B) 2.8
C) 3.6
D) 2.7
E) 1.1
72 --- 5 2.7S = 14.4   ? ---- 1   45 ---- 5 US = 9   ? ---- 1 S = ?   S = (14.4 - 9)/2= 
<gadget id="calculator">(14.4 - 9)/2</gadget>
<output>2.7</output>
2.7   Answer:2.7
<result>D</result>
A man swims downstream 72 km and upstream 45 km taking 5 hours each time; what is the speed of the current?