Ruchika and her friends went on a trip. She slept in a conical tent. They discovered that the diameter of their conical tent is 4.2 m. One of her friends observed the
tent's packing, which stated that the volume of the tent is 12.936 m^3 and it's height is 2.8 m and slant height is 3.5 m, which piqued the children's interest in learning more about the conical tent they were carrying.
Based on the above information, answer the following question:
What would be the curved surface area of the conical tent?