C. C and Pb; Carbon and Lead being in the same group.
1. For this question, the adjective small must be percepted in a relative sense. This is because it is not the smallest ion (that would be hydrogen). It could be that the antimony and beryllium ions are smaller compared to their neutral forms. This is because they donate electrons when ionized. As a result, the electrons are reduced, so does the electron cloud which makes the radius much smaller.
2. The periodic table is arranged in terms of increasing atomic number. For neutral atoms, the number of protons (atomic number) is equal to the number of electrons. So, the farther we go down the table, the higher the atomic number. The higher the atomic number, the bigger the electron cloud which makes the atomic radius bigger. Because by definition, atomic radius is the length from the nucleus to the farthest electron from the nucleus.
A plant's circulatory system is the way for a plant to get carbon dioxide and nutrients to every cell in its system. It is also the way for a plant to get rid of toxins and waste from its system. In a plant's circulatory system, the nutrients a plant needs to survive travels upwards from the roots of the plan to the rest of it's system, and the toxins and waste is secreted from its extremeties located above the ground.
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Physical, since you are physically changing its appearance
