Sig figs

[Angad Beniwal 1J]

If we are doing a calculation such that we end up carrying out the following division:

(.10)/(250) = 0.0004

Do we leave the value as 0.0004 (which is what our calculator gives), or do we add a zero to make it 0.00040 so that it has two sig figs just like the original values?

Additionally, how do we know which values affect sig figs?
for instance, if the problem states that there are 0.40M at 1 hour, and we multiply 1 hour and 0.40 M, do we treat the value "1 hour" or 60 minutes as having one sig fig or do we treat it as an exact value and disregard any effect it would have on the sig figs of the product?

[Emily Chu 3E]

You would add a zero so that there are two sig figs.

Also, Im unsure about your second question but if 1 hr was a conversion factor, then you would disregard it.

[Laila Sathe 1D]

do you know what lavelle's policy is with temperature sig figs? a ta mentioned that we should ignore sig figs in temperature.