Find the area of the circle with the given radius or diameter. Use "3.14" for . Round your answer to the nearest tenth.
Diameter = 42.0 mm
Radius = Diameter / 2
Radius = 42.0 mm / 2
Radius = 21.0 mm
Area = π * (radius)^2
Area = 3.14 * (21.0)^2
Area = 3.14 * 441
Area = 1385.94 mm^2
Therefore, the area of the circle with a diameter of 42.0 mm is 1385.9 mm^2.