Concentration of Solutions is oftenly expressed in Molarity. Molarity is the number of moles of solute dissolved per volume of solution.
Molarity = Moles / Volume
As,
Moles = Mass / M.mass
So,
Molarity = Mass / M.mass × Volume ---- (1)
Data Given;
Volume = 0.750 L
Mass = 52 g
M.mass = 180 g/mol
Putting Values in eq.1,
Molarity = 52 g ÷ (180 g.mol⁻¹ × 0.750 L)
Molarity = 0.385 mol.L⁻¹
I used an online calculator and got 54.22 m/s. I hope that helps
I don’t really have a clear answer for you but this might help
Answer: the boiling point elevation constant is 
Explanation:
Elevation in boiling point is given by:

= Elevation in boling point
i= vant hoff factor = 1 (for non electrolyte)
=boiling point constant = ?
m= molality

Weight of solvent (diethylether)= 330 g = 0.33 kg
Molar mass of solute (benzophenone)= 182 g/mol
Mass of solute (benzophenone) = 38.2 g


Thus the boiling point elevation constant is 
You may want to ask the questions seperatly more likely for someone to answer