8. A pyramid has a square base of side 25 cm and the slant height of each triangular face is 18 cm. What is the surface area of the pyramid? A. 1.025 cm² B. 1.155 cm² C. 1.255 cm² D. 1.525 cm² 9. What is the total surface area of a sphere whose radius is 9 cm?
A. 1.017.36 cm²
B. 1.071.36 cm²
C. 1.107.36 cm²
D. 1.170.36 cm²
10. A pyramid has a square base of side 21 cm and the slant height of each triangular
face is 15 cm. What is the surface area of the pyramid?
