To rectify ”loose threads,” trim off the thread remains as near to the article as possible. Loose threads can detract from the overall appearance of the embroidery and lead to unraveling over time. Neatly trimming these threads ensures a clean finish and enhances the quality of the embroidery. It is essential to use sharp scissors to avoid damaging the fabric while trimming the threads.
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.