(a)
Curved Surface Area = (pi rl)
(115.5 = frac{22}{7} times r times 10.5)
(115.5 = 33r)
(r = frac{115.5}{33} = 3.5 cm)
(b)
(therefore h^{2} + (3.50)^{2} = (10.5)^{2})
(h^{2} = 10.5^{2} – 3.5^{2})
(h^{2} = 98 implies h = sqrt{98})
(h = 9.8994 cm approxeq 9.90 cm)
(c) Volume of a cone = (frac{1}{3} pi r^{2} h)
= (frac{1}{3} times frac{22}{7} times frac{7}{2} times frac{7}{2} times 9.90)
= (frac{23.1 times 11}{2})
= (127.05 cm^{3} approxeq 127 cm^{3})