It would be 33.3 grams. Let me explain:
First, you want to get the molar mass of NI3 (394.7 grams). Next, divide 30 grams of NI3 by the molar mass to get 0.076 mols. After that, mole ratio into 3IF (multiply the mols of NI3 by 3, divide by 1) and get .228 mols of IF. After, find IF’s molar mass (145.89 grams) and multiply the mols of IF by its molar mass to get 33.26 grams. Remember, use 3 sig figs. Those sig figs would round the 33.26 to 33.3 grams. Hope this helps!