Hey just been pondering over this question for a while some help would be greatly appreciated.
"Under what circumstances would you expect a cell to increase the amount
of its smooth endoplasmic reticulum?"
So my ideas
= Increase in presence of drugs/poisons as the Smooth ER has the function of detoxifying drugs and poisons, a cell such as a liver cell will thus require a lot more Smooth ER in these types of conditions (to prevent damage)