Question

my question needs to be atleast 20 characters long but I think the picture explains it, I need help on q.8 :)

Answer 1

use a ruler . put it on the paper .(i measured it on the screen and it was 4 cm )
it means that 4 cm in the picture is 0.1 mm in reality .
so ,magnification is 4/0.1=40 times