Everyday Science

Ombrophobia is the fear of rain. The term comes from Greek roots where 'ombro-' means rain and '-phobia' means fear.

Vitamin B12 contains the metal cobalt as a central component of its structure, which is essential for its biological activity.

A simple microscope uses a convex lens to magnify objects. Convex lenses converge light rays to form a magnified virtual image, which is why they are used in simple microscopes.

Niacin is the common name for vitamin B-3, which is essential for energy metabolism and DNA repair. Therefore, vitamin B-3 corresponds to Niacin.

Tooth decay is primarily caused by sugar, which bacteria in the mouth metabolize to produce acids that erode tooth enamel. The other options do not contribute to tooth decay.

The three basic units of measurement in the metric system are the metre (for length), litre (for volume), and gramme (for mass). These are the fundamental units commonly taught as the basis of the metric system.

The dates when day and night are approximately equal are called equinoxes, which occur around March 20 and September 23 each year. These dates mark the beginning of spring and autumn respectively in many parts of the world.

The luster of a diamond is primarily due to total internal reflection, where light entering the diamond is reflected multiple times inside before exiting, giving it its characteristic brilliance and sparkle.

Nephology is the scientific study of clouds, making option B the correct answer. The other options do not relate to the definition of nephology.

In additive color mixing, combining red, green, and blue light produces white light. This is the basis of how screens display colors using RGB values.