The correct answer would be b. However they are also all numbered. But the correct answer is B Chemical Symbols.
The answer is 0.25 g/cm3
The equation for finding density is mass divided by volume.
Therefore,
12 grams/ 49 cm3= 0.24489795918367 gram/cubic centimeter
you would then round this to the nearest significant figure which is the number of significant numbers you have and the highest amount of sig figs present in this equation is two sig figs. That means that you would round your answer, becasue it has a zero before the decimal which doesn't count as a significant figure, to the nearest hundredth which would be 0.25 and then you add your value after it which is g/cm3
Answer:
Nuclear fusion plays an important role in making elements that are heavier than helium.
Explanation:
Nucleosynthesis is the process by which new atomic nuclei are created from pre-existing nucleons (protons and neutrons) and nuclei. According to current theories, the first nuclei were formed a few minutes after the Big Bang, through nuclear reactions in a process called Big Bang nucleosynthesis.
In order to synthesize a new element, there must be a change in the number of protons. We should remember that elements are known by the number of their protons as it represents their atomic number.
Elements heavier than helium are formed by nuclear nucleosynthesis in which nuclear fusion plays a very crucial role as typified by the equations shown in the question.

Actually Welcome to the Concept of the Ionic bonds.
Since Sodium (Na) is a cation and Chlorine (Cl) is a Anion, they both form a Ionic bond called as NaCl (common salt)
So answer is, Na and Cl
Answer:
HCl (aq) + NaOH (aq) --> H2O (L) + NaCl (aq)
Explanation:
HCl is a strong acid while NaOH is a strong alkali. Hence both should dissociate completely in water and 1 mol of HCl will fully neutralise 1 mol of NaOH.
I'm assuming that Part 2 on molarity is part of a data based question that requires you to calculate the number of moles of NaOH based on the data provided and the equation that you are required to balance. Hence, I can't help you with it as I do not have the values.