Matthew went to a bank to withdraw ^@ ₨ 13000^@. He asked the cashier to give ^@₨ 500^@ and ^@₨ 1000^@ notes only. Matthew got ^@16^@ notes in all. Find the number of ^@₨ 500 ^@ and ^@₨ 1000^@ notes he received.
A wooden article was made by scooping out a hemisphere from each end of a cylinder as shown in the figure. If the height of the cylinder 21 cm and its base is of radius 5 cm, then the total surface area of the article when it is ready is: