In how many seconds will a train 180 meters long pass an oak tree, if the speed of the train is 54 km/hr?	Choose the correct answer:
A) 10
B) 12
C) 14
D) 16
E) 18
speed = 54 * 5/18= 
<gadget id="calculator">54 * 5/18</gadget>
<output>15</output>
15 m/s   time= 180/15= 
<gadget id="calculator">180/15</gadget>
<output>12</output>
12 seconds   The answer is 12.
<result>B</result>
In how many seconds will a train 180 meters long pass an oak tree, if the speed of the train is 54 km/hr?