OPTICS>>>>>>>>

it consists of 3 steps ..... refraction , reflection , refraction ......

1/v + 1/8 = 1/10

1/v = 1/10 - 1/8

1/v = -2/80

v= -40cm ...........

now it reflects ..

so v = 40cm behind mirror ......

now it refracts again ...

1/v + 1/40 = 1/10

1/v = 1/10(3/4) ..

v = 40/3cm in above of the lens ....

kindly post optics questions in optics section ...