The measurements below were made on four different balances:

i$.12\mathrm{.}5g$

ii$.12\mathrm{.}33g$

iii. $12\mathrm{.}5201g$

iv$.12\mathrm{.}490$

A student takes a reading from a balance where the display fluctuates between $12\mathrm{.}51g$ and $12\mathrm{.}55g.$ Which of the four balances above was used?

ii

iii

iv

i