D! Predictable and controlled
Answer:
C,,, Plants are already present.
Explanation:
For photosynthesis to occur, plants need sunlight, water, carbon dioxide and chlorophyll. Through the process of photosynthesis plants convert light energy into chemical energy. They use this energy to make food which they store as sugars.
The equation is balanced because the mass and charge are equal on both sides of the reaction equation.
In a nuclear reaction, one nucleus is transformed into another. In this case of the equation shown, the radon nucleus is being transformed into a polonium nucleus with the emission of an alpha particle.
The equation is balanced because a total mass of 219 is found on both sides of the reaction equation and a total charge of 86. Recall that an alpha particle is the same as a helium nucleus with a mass of four units and a charge of two units.
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