The surface charge density of a thin charged disc of radius R is $\sigma$. The value of the electric field at the centre of the disc is $\frac { \sigma } { 2\epsilon _ { 0 } }$. With respect to the field at the centre, the electric field along the axis at a distance R from the centre of the disc:\\
(1) reduces by $70.7\%$\\
(2) reduces by $29.3\%$\\
(3) reduces by $9.7\%$\\
(4) reduces by $14.6\%$