Average speed is defined as the ratio of total distance covered in total given time
here we know that total distance that man moved is
so total distance is
now here total time of the motion is
total time will be given as
now by above formula
so his average speed is 30 km/h
The nebular theory describes the formation of the solar system and states that the system began as a gigantic cloud of gas and dust called a nebula which eventually condensed to form the sun, planets and other objects in the solar system. The first fact speaks to the formation of the planets, where gravity pulled larger clumps of material closer to form solid rocky planets closer to the sun and gas giants further out. The second requirement is that a nearby explosion or super nova would have to disturb our nebula to trigger rotation and the eventual formation of the sun. The third requirement/fact is that the planets go around the sun in the same direction. the last fact is that the planets go around the sun within 6 degrees of a common plane. This indicates that the solar system formed from a spinning disk of materials.
Answer:
I really don't know. I think it's E.Current
sorry if I'm wrong
B is the correct answer hope that helped
