What is the formula for chemical spill mix?

A. sodium carbonate, bentonite and sand, proportional by mass
B. sodium bicarbonate, bentonite and sand, proportional by mass
C. sodium carbonate, bentonite and sand, proportional by volume
D. sodium bicarbonate, bentonite and sand, proportional by volume

(I didn't know the answer, either. There goes 1 mark on the final exam.)

Now it's time to rush and finish my cover letter and autobiographical statements for the teaching jobs I am applying for.