1. is 7,9-di-tert-butyl-1-oxaspiro[4,5]de ca-6,9-diene-2,8-dione toxic? and why 2. is 2-(2-butoxyethoxy)ethoxy , TMS derivative toxic and why?
3. is pentasiloxane, dodecamethyl toxic and why?

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be

< > according to newton's third law of motion, forces always act in equal but opposite pairs. another way of saying this is for every action, there is an equal but opposite reaction.< >