B, E, F have 3 significant figures
(a) 43.6 mg; (b) 520 mg
(a) <em>Mass of phosphoric acid (PA) in a dose
</em>
Mass of PA = 2 tsp × (21.8 mg PA/1 tsp) = 43.6 mg PA
(b) <em>Mass of PA in the bottle
</em>
<em>Step 1</em>. Convert <em>ounces to millilitres
</em>
Volume = 4 oz × (30 mL/1 oz) = 120 mL
<em>Step 2.</em> Calculate the mass of PA
Mass of PA = 120 mL × (21.8 mg PA/5 mL) ≈ 520 mg PA
