Answer: A) REM rebound Explanation:

Answer: B) Lungs Explanation: Emphysema is a condition that involves damage to the walls of the air sacs (alveoli) of the lung i.e, primarily causes shortness of breath due to over-inflation of the alveoli.   First, emphysema causes holes to gradually form inside the lungs' air sacs, thereby weakening their internal structure and inhibiting the exchange of oxygen and carbon dioxide.

Answer: D) ATP, Water Explanation: Cellular respiration is the three-step process by which cells make ATP using glucose and oxygen. Oxygen and glucose are both reactants in the process of cellular respiration. The main product of cellular respiration is ATP, waste products include carbon dioxide and water.

Answer: A) if all the resources of an economy are in use, more of one good can be produced only if less of another good is produced. Explanation: A graph that describes the maximum amount of one good that can be produced for every possible level of production of the other good is nothing but a production possibilities curve.

A Bath towel or a tea bag are suitable answers.

Answer: D) All the above Explanation: Carbohydrates, together with lipids, proteins and nucleic acids, are one of the four major classes of biologically essential organic molecules found in all living organisms. They not only provide energy for vital metabolic reactions but also supply the building materials for normal structure, growth and repair. Your body needs relatively large quantities of carbohydrates, fats and protein for optimal function, hence their classification as macronutrients.

Answer: C) Fluorine Explanation: Electronegativity refers to the ability of an atom to attract shared electrons in a covalent bond. The higher the value of the electronegativity, the more strongly that element attracts the shared electrons. Electronegativity increases from bottom to top in groups, and increases from left to right across periods. Thus, fluorine is the most electronegative element and lithium is the least.

In Greek, the meaning of Menarche is Beginning.   Menarche is the first menstrual cycle, or first menstrual bleeding, in female humans. From both social and medical perspectives, it is often considered the central event of female puberty, as it signals the possibility of fertility.