Physics
A small drop of oil spreads over water because :

Water has a higher surface tension
Oil has a higher viscosity
Water has a higher viscosity
Oil has a higher surface tension

ANSWER DOWNLOAD EXAMIANS APP

Physics
We always see the same face of the moon, because

It takes equal time for revolution around the earth and rotation on its own axis
It is smaller than the earth
It rotates at the same speed as the earth around the sun
It revolves on its axis in adirection opposite to that ofthe earth

ANSWER DOWNLOAD EXAMIANS APP