Answer:
(d) (2.54 cm)/(1 in)
Explanation:
You want to find the conversion factor that can be used to convert inches to centimeters.
Conversion factor
Your number in inches must be multiplied by a fraction that cancels inches and leaves centimeters. That means it will have cm in the numerator, and in in the denominator.
The value of the fraction must be 1, so the number of cm in the numerator must be equal in length to the number of in in in the denominator. We know that 2.54 cm = 1 in, so the fraction can be ...

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Additional comment
The conversion is ...
