A student performed the experiment of determination of focal length...

A student performed the experiment of determination of focal length of a concave mirror by $u-v$ method using an optical bench of length $1.5 \mathrm{~m}$. The focal length of the mirror used is 24 $\mathrm{cm}$. The maximum error in the location of the image can be $0.2 \mathrm{~cm}$. The 5 sets of $(u, v)$ values recorded by the student (in $\mathrm{cm})$ are : $(42,56),(48$, $48),(60,40),(66,33),(78,39)$. The data set(s) that cannot come from experiment and is (are) incorrectly recorded, is(are)