Matilda Loisel, in Guy De Maupassant’s ”The Necklace,” begins as a discontented and materialistic woman, dissatisfied with her modest life and dreaming of wealth and luxury. She borrows a beautiful necklace to attend a high-society event, only to lose it. Faced with the consequences, she and her husband sacrifice everything to replace it, living in poverty for ten years. During this time, Matilda transforms. The hardship forces her to work hard and endure suffering, leading her to develop a more realistic understanding of life. When she learns that the necklace was a fake, her character arc reaches its climax—she has gone from vanity and superficiality to a deep appreciation of life’s true value.
On the day of her examination, Riya sharpened her pencil from both ends as shown below. 
The diameter of the cylindrical and conical part of the pencil is 4.2 mm. If the height of each conical part is 2.8 mm and the length of the entire pencil is 105.6 mm, find the total surface area of the pencil.
Two identical cones are joined as shown in the figure. If radius of base is 4 cm and slant height of the cone is 6 cm, then height of the solid is