Acoral reef grew 20.2mm taller. how much did it grow in meters?

  Growth of coral reef in meters = 0.0202 m= 2.02 x 10⁻²m

Explanation:

 1 meter = 100 cm

 1 cm = 10 millimeter

 1 meter = 100 x 10 = 1000  millimeter.

 1 millimeter = 1/1000 = 0.001 meter.

 A coral reef grew 20.2mm taller = 20.2 x 0.001 m

                                                  = 0.0202 m

 Growth of coral reef in meters = 0.0202 m= 2.02 x 10⁻²m

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