Questions

The HF band is based on frequencies 3 to 30 Mhz. AM radio stations are in the HF band but normally are stated in kilohertz.

Jean Piaget was a cognitive psychologist who identified four stages of development: the sensorimotor stage from birth to 2 years, the preoperational stage from age 2 to age 7, the concrete operational stage from age 7 to 11, and the formal operational stage from age 11 to adult. He identified milestones that occur at each stage.

According to Piaget, the main task of the sensorimotor stage is for the child to learn the concept of object permanence, use senses and motor skills to understand the world.

The Study of Blood is called as Hematology which involves treating diseases that affect the production of blood and its components, such as bloodcells, hemoglobin, blood proteins, bone marrow, platelets, blood vessels, spleen, and the mechanism of coagulation.

The Ganges, Brahmaputra delta covers an area of about 75000 sq km.

J. J. Thomson discovered electrons in the year 1897.

Ernest Rutherford discovered protons in 1911.

James Chadwick discovered neutrons.

Al Aziziyah, the hottest place on earth is located in Libya, in North Africa. On 13 September 1922, a high temperature of 58.0 °C was recorded in Al Aziziyah.

This is considered the highest temperature ever measured on Earth.