Question

What is the surface area of a cylindrical ring if its outside diameter is 16 mm and its inside diameter is 10 mm? Round your answer to the nearest whole number. A. 123 mm2 B. 118 mm2 C. 92 mm2 D. 385 mm2

Answer 1

The answer is 385 mm2 i took the test.

Answer 2

Assuming height is roughly equal to zero (shape is flat)

Area of larger circle: πr² = 64*π = 201.06 m²
-Area of smaller circle πr² = 25π= -78.54
=Area of ring (rounded to nearest integer) = 123 mm²

Answer is A) 123 mm²