Europe and North America are moving apart at 2 cm per year. Find (or estimate) the width of the North Atlantic Ocean and determine how long ago the North Atlantic began to form. Use Wikipedia to find the size of the Atlantic.
Width = 2,848 km = 2,848,000 m 2,848,000 m * 100 = 284,800,000 cm If Europe and North America are moving apart at 2 cm per year: 284,000,000 : 2 = 142,400,000 years Answer: The North Atlantic Ocean began to form 142,400,000 years ago.