In an experiment to find out the diameter of wire using screw gauge, the following observations were noted :
(A) Screw moves $0.5 \mathrm{~mm} on main scale in one complete rotation
(B) Total divisions on circular scale =50
(C) Main scale reading is 2.5 \mathrm{~mm}
(D) 45^{\text {th }}$ division of circular scale is in the pitch line
(E) Instrument has 0.03 mm negative error
Then the diameter of wire is :