Impulsive buying refers to making purchases without pre-planning, often triggered by emotional appeal or attractive displays in the store. Retailers design layouts and offers to encourage customers to make unplanned purchases.
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.