A rare rock formation on Continent A is found 300 km from a matching formation on Continent B. Continent A is part of a plate that is moving at a rate of 36 mm/year. How many years ago were the matching formations separated

c. 8,300,000 years

Explanation:

In the context, it is given that a rare rock formation process that is formed on the continent A is formed about 300 km from the same rare formation on the continent B.  Now the continent A is moving at the rate of 36 millimetre per year.

Now rock formation takes place many many years to form. In this the rare formation of rock were separated at around 8,300,000 years.