A container, opened from the top and made up of a metal sheet, is in the form of a frustum of a cone of height 16cm with radii of its lower and upper ends as 8cm and 20cm, respectively. Find the cost of the milk which can completely fill the container, at the rate of ? 20 per litre. Also, find the cost of metal sheet used to make the container, if it costs Rs.8 per 100cm2.(Take π= 3.14)