Calculating Moles/ masses?

Question

Can someone please show me step by step how to calculate the following... (It's not for an assignment, I just can't pick it up the way the teacher was showing me)

1. How many moles:

50cm^3 of 0.75 M NaOH(aq)

2. What weight of solid KOH would you require to prepare the following:

150cm^3 of a 0.75M aqueous solution

Answer 1

1-moles in 50cm^3 of 0.75 M NaOH(aq) :

1 cm^3 = 1 mL

50cm^3= 50 mL = 0.05 L

molarity = moles/ litres

>> moles = molarity  X litres

= 0.75 X 0.05 = 0.0375 mole

2-  weight of KOH :

Weight = moles X molecular weight

molecular weight of KOH =39.1 +16 +1 =56.1 g/mole

moles of KOH = molarity X litres = 0.75 X 0.15 = 0.1125 mole

Weight  of KOH =  0.1125 X 56.1 =6.31 g