Answer:
Calcium is a chemical element with the symbol Ca and atomic number 20.
Explanation:
Vestigial structures are considered evidence since scientists believe they are structures that were once used by a species ancestors but are no longer needed. They do not impair the organisms in any way, so there is no need for evolution to get rid of them. Vestigial structures are anatomical features that no longer seems to have a function or purpose in the current form of an organism of the given species. Examples are wisdom teeth, the muscles of the ear, the appendix, the tail bone among others in human.
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The apple pudding which is prepared by the combination of the sugar, apples, lemon juice, and butter belongs to the category of mixture. Since, multiple substances are included in the apple pudding recipe, it falls under the category of elements. A mixture can be defined as the substance which is formed by the mixing of the two or more than two substances. A compound can be defined as anything which is composed of two or more than two elements. . On the other hand, an element can be defined as the substance which have the same atoms present in it. Atom is the smallest constituent having chemical properties. and a group of atoms is known as molecules. Hence, an apple pudding is a mixture.