Explanation : Projected visual aids are pictures shown upon a screen by use of a certain type of machine such as a filmstrip projector, slide projector, overhead projector or TV NCR. The overhead Projector (OHP) is most used in all Audio-video aids. It projects transparencies with brilliant screen images suitable for use in a lighted room.
Explanation : Some of the characteristics of a good question paper is-Validity, Reliability, Practical, relevant, balanced, appropriate in difficulty, clear, authentic, objective and economical.
Explanation : Characteristics of a Family • A family is based on marriage, which results in a mating relationship between two adults of opposite sex. • A family is generally limited in size, even large, joint and extended families. • The family is a unit of emotional and economic cooperation. • Each member of family shares duties and responsibilities. • They use same house, food and perform common social activities.
Explanation : Vermicompost is the product of the compositing process using various species of worms, usually red wigglers, white worms and other earth worms, vermicompost is an excellent nutrient-rich organic fertilizer.