The period of diffused light between sunset and complete darkness is called ……………. .

1. dawn
2. dusk
3. twilight
4. Both (2) and (3)

The duration of twilight :

1. increases to the poles
2. might last for as much as 7 weeks at the poles
3. is as long as the sun is 18° below the horizon
4. all of the above.

Greenwich Mean Time : …………… :: Indian Standard Time : 12:00 pm

1. 6:30 am
2. 5:30 am
3. 6:30 pm
4. 5:30 pm

Assertion (A): Phenomena of dawn and dusk is experienced more in temperate regions.

Reason (R): The twilight continues as long as sun is 18° below the horizon.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R does not explain A.
3. A is true but R is false.
4. A is false but R is true.