The ear canal in humans is a hollow tube leading from the outer ear to the eardrum. In an adult human, the length of the canal is approximately 2.5 cm. Estimate the diameter of the canal and compute its approximate area (in cm²).
a) Diameter ≈ 0.89 cm, Area ≈ 0.625 cm²
b) Diameter ≈ 1.59 cm, Area ≈ 2.0 cm²
c) Diameter ≈ 1.12 cm, Area ≈ 0.985 cm²
d) Diameter ≈ 2.0 cm, Area ≈ 3.14 cm²