a person travels from his house to office from 11:00am to 11:30 am and covers a distance of 20km. find the average speed of the person.  Options:
A) 20.1km/h  B) 20.5km/h  C) 21.1km/h  D) 10km/h  E) 20.9km/h
time=11:30-11:00=30min=1/2hour   distance=20km   speed=20*1/2= 
<gadget id="calculator">20*1/2</gadget>
<output>10</output>
10km/h   ANSWER:10km/h
<result>D</result>
a person travels from his house to office from 11:00am to 11:30 am and covers a distance of 20km. find the average speed of the person.