For a solar eclipse t occur;
C. The moon is located from a line between the sun and earth
Chemical equation is the symbolic representation of chemical reactions.
Explanation
Chemical reactions are known as the reaction where two or more molecules or compounds react with each other leading to formation of product compounds along with either release or absorption of energy.
The symbolic representation of the processes occurring in a chemical reaction is termed as chemical equation.
The symbolic representation includes the reactants, products, external energy type and quantity of external energy and also about release of energy if occurs.
So the reactants are usually written in the left side of the chemical equation whereas on the right the products are written.
Both the sides are linked by a single headed arrow mark.
Some both the sides are linked by double heated arrow mark indicating the equilibrium chemical reaction.
A drought is a period of drier-than-normal conditions that results in water-related problems.<span> When rainfall is less than normal for several weeks, months, or years, the flow of streams and rivers declines, water levels in lakes and reservoirs fall, and the depth to water in wells increases.</span>
Hepta is seven and tetra is four, so option c is your answer
A chemical element is a substance that is made up of only one kind atom.