A screw gauge of pitch $0.5 \mathrm{~mm}$ is used to measure the diameter of uniform wire of length $6.8 \mathrm{~cm}$, the main scale reading is $1.5 \mathrm{~mm}$ and circular scale reading is 7 . The calculated curved surface area of wire to appropriate significant figures is :

[Screw gauge has 50 divisions on its circular scale]