1. Here is a sector, $AOB$ , of a circle with centre $O$and angle $AOB$= $x^{\circ}$

The sector can form the curved surface of a cone by joining $OA$to $OB$ .

The height of the cone is $25cm$.
The volume of the cone is $1600{cm}^{3}$

Work out the value of $x.$
Give your answer correct to the nearest whole number.

$x=$.......................