Question

Choose the more precise measurement 6 cm or 2.5 cm

Answer 1

How precise a measurement is is determined by how many numbers after the decimal that it has.

Answer 2

Almost. The precision is related to the number of significant digits. 6 is between 5.5 and 6.5, an uncertainty of +- 0.5 or a percent uncertainty of 0.5/6(x100%) = 8.3%

2.5 is between 2.45 and 2.55 , an uncertainty of +- 0.05 or
a percent uncertainty of 0.05/2.5 (x100%) = 2%.

6. has 1 significant digit
6.0 or 25 or 2.5 has 2 significant digits and is more precise

Answer 3

This is why I fanned you.