Which if the following is a requirement that units in a correct formula or equation must always satisfy?
a) each unit in the formula, expressed in si base units, must be the same.
b) all units must be units only of mass, length, or time.
c) the units on both sides of the equal sign, expressed in si base units, must be the same.
d) all masses must be in kilograms, all lengths in meters, and all times in seconds.

Acommon technique in analysis of scientific data is normalization. the purpose of normalizing data is to eliminate irrelevant constants that can obscure the salient features of the data. the goal of this experiment is to test the hypothesis that the flux of light decreases as the square of the distance from the source. in this case, the absolute value of the voltage measured by the photometer is irrelevant; only the relative value conveys useful information. suppose that in part 2.2.2 of the experiment, students obtain a signal value of 162 mv at a distance of 4 cm and a value of 86 mv at a distance of 5.7 cm. normalize the students' data to the value obtained at 4 cm. (divide the signal value by 162.) then calculate the theoretically expected (normalized) value at 5.7 cm.