Answer
im not quite sure but I think the answer is <em>D atom</em><em> </em>
Explaination
Answer:
0.9%
Explanation:
At the instance where you add RBCs to a solution of 0.9% NaCl, they will maintain their shape as well as their size, this is simply to indicate an equilibrium. That entails that the solution is isotonic to the RBCs. This must mean that the concentration of solutes on each side must be equal otherwise osmotic pressure would force water either in or out of the membrane. Therefore, one can also safely assume that RBC's also have a solute concentration of 0.9%.
Answer:
(a) 
(b) Rubidium
Explanation:
Hello,
This titration is carried out by assuming that the volume of base doesn't have a significant change when the mass is added, thus, we state the following data a apply the down below formula to compute the molarity of the base solution:

Solving for the molarity of base we've got:

Now, we can compute the moles of the base as:

(a) Now, one divides the provided mass over the previously computed moles to get the molecular mass of the unknown base:

(b) Subtracting the atomic mass of oxygen and hydrogen, the metal's atomic mass turns out into:

So, that atomic mass dovetails to the Rubidium's atomic mass.
Best regards.