Answer:
16,,24Mg 17,,a24.1 18a mass number of the most abundant isotope
Explanation:
atomic number of Mg is 12 ,therefore its mass number should be the value that is very close to 24.
24.1 is the value of thee most abundant isotope.
Assuming this is a true or false question, the answer would be True
Answer: The missing coefficient is 2.
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

As in the products, there are 2 atoms of sodium, thus there will be 2 atoms of of sodium in the reactant as well. This will balance the number of hydrogen and oxygen atoms as well.
Thus the missing coefficient is 2.
A less intense wave will have fewer OSCILLATING AMPLITUDE than a more intense wave.
The intensity of a wave is the power transferred per unit area, where the area is measured on the plane perpendicular to the direction of propagation of the energy. Intense sounds are characterized by the particles of the medium vibrating back and forth with large amplitude.<span />
Ernest Rutherford i believe