The elements in the middle of the periodic table are called ________.

Explanation

In the periodic table of elements, there are seven horizontal rows of elements called periods. The vertical columns of elements are called groups, or families. The transition metalsmake up the middle block of the periodic table. The transition elements or transition metals occupy the short columns in the center of the periodic table, between Group 2A and Group 3A. They are sometimes called the d-block elements, since in this region the d-orbitals are being filled in, and are also referred to as B-group elements since in most numbering systems of the columns on the periodic table the numerals of these groups are followed by the letter B. 92. Answer: a Explanation: The correct answer is Food chain. Key Points Food chain: A food chain shows the feeding relationship between different organisms in a particular environment and/or habitat. A food chain shows how energy is passed from the sun to producers, from producers to consumers, and from consumers to decomposes such as fungi. They also show how animals depend on other organisms for food. Only 10% of energy is transferred to higher levels from the previous one. So, the demand for food is more in higher levels. So, the food chain does not go for more than 3-4 tropic levels. This leads to more complex food forms known as a food web. Primary (100%) → First level/ Primary (10%) → Second-level/ Secondary (1%) → Third level / Tertiary (0.1%). Additional Information Food web is a network of food chains where all the chains are naturally interconnected. The flow of energy in a food chain is unidirectional, once it reaches the next tropic level it does not come back again. 93. Answer: a Explanation: The United Nations Children's Fund is a United Nations program headquartered in New York City that provides humanitarian and developmental assistance to children and mothers in developing countries. Digital Gender Atlas has been developed to identify the low performing geographic pockets for girls, particularly from marginalized groups such as scheduled castes, scheduled tribes, and Muslim minorities, on specific gender- related education indicators. With the support of UNICEF, atool has been developed which will help identify low performing geographic pockets for girls, particularly from marginalized groups such as scheduled castes, scheduled tribes, and Muslim minorities, on specific gender-related education indicators.