Find the surface area of the triangular prism shown. The height is 21 cm. The base is an isosceles triangle with waist length of 10 cm and base length of 12 cm.
Please directly answer the question and provide the final value, e.g., 1, 2.5, 300.
Question: Find the surface area of the triangular prism shown. The height is 21 cm. The base is an isosceles triangle with waist length of 10 cm and base length of 12 cm.
Please first conduct reasoning, and then answer the question and provide the final value, e.g., 1, 2.5, 300, at the end.
Question: Find the surface area of the triangular prism shown. The height is 21 cm. The base is an isosceles triangle with waist length of 10 cm and base length of 12 cm.