12. Half the height of 8 cm is 4 cm. Volume = 4 * 6 * 10 = 240 cm³, Option D
13. Double the dimensions you get 8 cm for the height, 6 cm for the radius. Then plug in. V = pi * (6)² * 8 >> pi * 36 * 8 = 288pi or ≈ 904.78, Option C 14. Half of all the dimensions are 1 in, 4 in, and 3 in. 1 * 4 * 3 = 12 in³, Option B 15. >> 16x = 180 >> x = 11.25 so Option B 16. Option D, 10 cm. 17. Option C, 8.5 in 18. Option B. 10.2 km 19. Option D. 0.82
20. cos 30 = b / 11.5 >> b = 11.5(cos (30)) = 9.96 m, Option C.