Researchers compare the body composition of cattle feeding on a grain diet with that of cattle feeding on a grass diet. this method of gathering data is classified as a. a census. b. a sample survey. c. an experiment. d. an observational study.

c. an experiment.

step-by-step explanation:

in an experiment, groups receive different treatments and the results are measured.   in this case, the treatment is the type of feed.

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have

middle maybe?

step-by-step explanation: