Which of the following represents an upside-down image? o a. +doo b. -doo c. +mo d.-m

D. -m

Explanation:

The magnification of an image is equal to the following ratio:

where

y' is the size of the image

y is the size of the real object

We have two situations:

- When m is positive, it means that y' has the same sign of y --> so the image has same orientation of the object (= image is upright)

- When m is negative, it means that y' has opposite sign to y --> so the image has opposite orientation to the object (= image is upside down)

So, the correct answer that describes an upside-down image is

D. -m

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