Chapter 4 - Section 4.5 - Concentration of Solutions - Checkpoint - Page 164: 4.5.1

d) 1.17 M

n (mol) = m (g) / Mw (g/mol), where Mw is the molecular weight of NaOH and equal to 40 g/mol → n = 58.5/40 = 1.4625 mol → M (molarity) = n / L , where L is the volume of solution, so M = 1.4625/1.25 = 1.17 mol/L