Two advantages of sustainable development are:
Conservation of resources: Sustainable development ensures the judicious use of natural resources like water, forests, and energy, preserving them for future generations. For example, promoting renewable energy sources like solar and wind power reduces dependency on fossil fuels.
Economic growth and stability: It helps in creating long-term economic opportunities through green industries, eco-friendly businesses, and employment in renewable energy sectors. This reduces poverty and enhances global economic stability.
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.