A train 640 m in length crosses a telegraph post in 16 seconds. The speed of the train is?	Choose the correct answer:
A) 22 kmph	B) 77 kmph	C) 144 kmph	D) 71 kmph	E) 88 kmph
S = 640/16 * 18/5= 
<gadget id="calculator">640/16 * 18/5</gadget>
<output>144</output>
144 kmph   Answer:144 kmph
<result>C</result>
A train 640 m in length crosses a telegraph post in 16 seconds. The speed of the train is?