The Atal Tunnel, also known as the Rohtang Tunnel, is a highway tunnel built under the Rohtang Pass in the eastern Pir Panjal range of the Himalayas, located on the Leh–Manali highway in Himachal Pradesh. Spanning a length of 9.02 km, it is the world’s longest tunnel situated above 10,000 feet and is named after the former Prime Minister of India, Atal Bihari Vajpayee. The cross-section of a tunnel is shown in figure. The radius of circular part is

Based on the above information, answer the following questions:
(iii) (b) What is the area of cross-section of the tunnel
(2)
Area of cross-section of the tunnel