A river flows at a velocity of 3 km/h relative to the riverbank. A boat moves upstream at a velocity of 12 km/h relative to the river. What is the velocity of the boat relative to the riverbank?

the answer would be   dignified - apex

blue light is scattered in different directions by the tiny molecules of air. blue is scattered more than other colours because it has a shorter distance to travel which results in smaller waves. this is why we see a blue sky most of the time.