how many mL of 2.0 M NaOH are required to get 100 g of NaOH?
How many moles are there in 100 g NaOH? That will be mole s= grams/molar mass = ??
Then M = moles/L. You know M and moles, solve for L and convert to mL.
Then M = moles/L. You know M and moles, solve for L and convert to mL.