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\(A B C D E F\) is the cross-section through the centre of mass of a uniform solid prism. \(A B C F\) is a rectangle in which \(A B = C F = 1.6 \mathrm {~m}\), and \(B C = A F = 0.4 \mathrm {~m}\). \(C D E\) is a triangle in which \(C D = 1.8 \mathrm {~m}\), \(C E = 0.4 \mathrm {~m}\), and angle \(D C E = 90 ^ { \circ }\). The prism stands on a rough horizontal surface. A horizontal force of magnitude \(T \mathrm {~N}\) acts at \(B\) in the direction \(C B\) (see diagram). The prism is in equilibrium.

1. Show that the distance of the centre of mass of the prism from \(A B\) is 0.488 m .
2. Given that the weight of the prism is 100 N , find the greatest and least possible values of \(T\).