A compound microscope consists of an objective less of focal length $2.0\;cm$ and an eye -piece of focal legth $6.25\;cm$ , separated by a distance of 15 cm . How far from the objective should an object be placed in order to obtain the final image at the least distance of distinct vision (25 cm) .

Question

$\begin{array}{1 1} u_0=2.59;M.p=13.51 \\ u_0=-2.59 ; M.p=20\\ u_0=1.59;M.p=12.51 \\u_0=-1.59;M.p=12.51 \end{array} $