problem 1:
A cone has a radius of 8 cm and an height of 11 cm.
a) calculate the lenght of the slent
b) calculate the surface area
c) calculate the volume
answer:
a) length of the slant:
s = √r² + h²
s = √(8² + 11²)
s = 13.6 cm
A: The length of the slant is 13.6 cm.
b) surface area:
A = r² * π + r * π * s
A = 8² * π + 8 * π * 13.6
A = 542.87 cm²
A: The surface area is 542.87 cm².
c) volume:
V = r² * π * h : 3
V = 8² * π * 11 : 3 (π = 3.1415..)
V = 737.23 cm³
A: The volume is 737.23 cm³.