Final answer:
When performing a unit conversion, we multiply by 1 in order to multiply by a conversion factor. Option C is correct.
Step-by-step explanation:
Unit conversions involve changing a value expressed in one type of unit to another type of unit. This is done by using conversion factors, which are ratios relating equal quantities of different units.
When performing a unit conversion, we multiply by 1 in order to multiply by a conversion factor. Multiplying by 1 doesn't change the value of the original number, but it allows us to introduce the conversion factor and multiply it by the original value. This helps us to convert the value from one unit to another without introducing any errors.
For example, if we want to convert 10 meters to centimeters, we use the conversion factor 1 meter = 100 centimeters. By multiplying 10 meters by the conversion factor, we get 10 meters * (1 meter/100 centimeters) = 1000 centimeters. The unit of meters cancels out, and we are left with the desired unit of centimeters.
Multiplying by 1 doesn't change the value of the original number, but it allows us to introduce the conversion factor and multiply it by the original value. This helps us to convert the value from one unit to another without introducing any errors.