An arch is in the form of a parabola with its axis vertical. The arch is 10 m high and 5 m wide at the base. How wide is it 2 m from the vertex of the parabola?

Question

$\begin {array} {1 1} (A)\;1.118\: m & \quad (B)\;2.23\: m \\ (C)\;1\: m & \quad (D)\;2\: m \end {array}$