Final answer:
A typical microdermabrasion treatment without a setting mask usually lasts 45 minutes, allowing enough time for effective exfoliation and skin rejuvenation.
Step-by-step explanation:
The typical duration for a microdermabrasion treatment when not using a setting mask is usually around 30 minutes to an hour. For most standard procedures, the answer would be (b) 45 minutes, which allows adequate time for the esthetician to perform the exfoliating process effectively on the client's skin. The goal of microdermabrasion is to rejuvenate the skin by removing the outermost layer of dead skin cells, leaving it smoother and promoting the growth of new, healthy skin cells.