<em>Hardness is a measure of how resistant solid matter is to various kinds of permanent shape change when a force is applied</em> <em>Macroscopic hardness is generally characterized by</em> <em>strong intermolecular bonds</em>, <em>but the behavior of solid materials under force is complex; therefore,</em> <em>there are different measurements of hardness</em>: <em>scratch hardness, indentation hardness, and rebound hardness. Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity. Common examples of hard matter are ceramics, concrete, certain metals, and super hard materials, which can be contrasted with soft matter.</em>
Answer:
<h2>Ethylene is a gaseous hormone in plants, it is a fruit ripening hormone.</h2>
Explanation:
Ethylene is a chemical signal through which ripening fruits trigger the ripening process in fruits, Studies on components of ethylene signaling have shown a linear transduction pathway leading to the activation of ethylene response factors. However, the whole pathway by which ethylene selects the ripening-related genes and interacts with other signaling pathways to regulate the ripening process still not yet fully known. Most fruits produce ethylene that starts the ripening process. Its level in under-ripe fruit is very low, but as fruit develop, the production of ethylene become larger that speed up the ripening process of fruit.
The source of the oxygen released into the air as a product of photosynthesis is C) Water only.