6 A projectile is fired from a point \(O\) on a plane which is inclined at an angle of \(20 ^ { \circ }\) to the horizontal. The projectile is fired up the plane with velocity \(u \mathrm {~ms} ^ { - 1 }\) at an angle of \(30 ^ { \circ }\) to the inclined plane. The projectile travels in a vertical plane containing a line of greatest slope of the inclined plane. The projectile hits a target \(T\) on the inclined plane.
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1. Given that \(O T = 200 \mathrm {~m}\), determine the value of \(u\).
2. Find the greatest perpendicular distance of the projectile from the inclined plane.
   (4 marks)
   
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