(i) To find the length of AB, use the formula for the chord length:

AB = 2 imes r imes ext{sin} rac{ heta}{2} = 2 imes 8 imes ext{sin} rac{2.4}{2} = 14.9 ext{ cm}.

(ii) The perimeter of the plate is the sum of the chord length and the arc length. The arc length is given by:

s = r heta = 8 imes (2 ext{π} - 2.4) = 31.1 ext{ cm}.

Thus, the perimeter is:

14.9 + 31.1 = 46.0 ext{ cm}.

(iii) The area of the plate is the area of the sector minus the area of the triangle. The area of the sector is:

rac{1}{2} imes r^2 imes heta = rac{1}{2} imes 8^2 imes (2 ext{π} - 2.4) = 124.3 ext{ cm}^2.

The area of the triangle is:

rac{1}{2} imes r^2 imes ext{sin} heta = rac{1}{2} imes 8^2 imes ext{sin} 2.4 = 21.6 ext{ cm}^2.

Thus, the area of the plate is:

124.3 + 21.6 = 146 ext{ cm}^2.