Final answer:
A standard iced espresso drink generally contains one to three shots of espresso, varying by size, with small having one shot, medium having two, and large having three.
Step-by-step explanation:
In terms of basic iced espresso drinks such as an Iced Americano or Iced Latte, typically a single shot of espresso is used for a small (tall) size, while a medium (grande) would have two shots, and a large (venti) may contain three shots.
This is a general guideline, though some coffee houses or baristas might alter the number of shots based on customer preference or specific drink recipes. When considering Starbuck's standards, you can expect these amounts to be consistent for an understanding of espresso shots in their iced beverages.