The natural source of light is :

1. candle flame
2. electric lamp
3. sun
4. kerosene lamp

The formation of inverted image in a pin hole camera shows that:

1. light enables us to see
2. light travels in a straight line path
3. light can pass through the pin hole
4. light does not pass through the pin hole

Umbra is a region of :

1. complete darkness
2. partial darkness
3. complete brightness
4. partial brightness

Penumbra is a region of :

1. complete darkness
2. complete brightness
3. partial brightness
4. none of the above