Explanation:
132.7425 g
a)
rounding to 3 decimal places :
Faith 132.743 g
rounding to the nearest gram :
Alfie 133 g
rounding to the nearest kilogram :
Sophia 0 kg
b)
Faith's suggestion is the most accurate.
as we can see, each adopted degree of accuracy gives us a larger or smaller error compared to the actual full value.
Faith's suggestion of 3 decimal places gives us an error of only 0.0005 g. but what it mean for the usual human observer ? does 132.743 g make any difference to 132.8 g or to 132.7425 g ? no. it typically causes a lot of effort to measure with high detail, but if there is no difference in the benefits in the value of that detailed information, it is not worth it.
Alfie's suggestion if rounding to the nearest gram gives us an error of 0.2575 g. does this make a difference to a human observer ? no. in fact, it makes it easier to understand. so, the tiny error is well worth it.
Sophia's suggestion gives us an error of the full 132.7245 g. so, a full 100% miss. the shown hamster has not a mass of 0. but that is what this suggestion actually tells us. so, that is too rough. we need a little bit more detailed information to be able to work with it.
so, Alfie's suggestion is the most appropriate, as a human being can mostly relate to a whole number of grams in this dimension. fractions of grams we cannot relate to. and kg for something that weighs only grams dies not give us any useful information either.