Wind is caused by

(A) Rotation of the Earth
(B) Revolution of the Earth
(C) Difference in atmospheric temperature
(D) Difference in atmospheric pressure

The answer is: (D) Difference in atmospheric pressure
Wind is caused by difference in atmospheric pressure.

When day and night are of equal length?

(A) 23rd February and 21st September
(B) 21st March and 23rd September
(C) 23rd March and 21st September
(D) 28th June and 26th December

The answer is: (B) 21st March and 23rd September
When the Sun is exactly above the Equator, it makes day and night of equal length. This event is called equinox and the two equinoxes occur in March (about 21st March) and September (about 23rd September).

In fish liver oil, there is:

(A) Vitamin A only
(B) Vitamin D only
(C) Vitamin A and Vitamin E
(D) Vitamin A and Vitamin D

The answer is: (D) Vitamin A and Vitamin D
In fish liver oil, there is Vitamin A and Vitamin D.