Length of the platform = 22 m

Circumference of semi-circle (c) = 11 m

height of the platform = 1.5 m

Rate of construction = Rs 4 per m^{3}

Length of the platform = 22 m

Circumference of semi-circle (c) = 11 m

height of the platform = 1.5 m

Rate of construction = Rs 4 per m^{3}