Scientists have estimated their age at between 400,000 and 800,000 years old.

American scientists have estimated that it would probably take 15 years and at least $3 billion to complete the project.

So far scientists have identified 140 of them and estimate there are about 200.

One scientist has estimated sea levels rose 50 feet in 300 years.

But American scientists have estimated the amount of oil at 28 billion barrels.

Scientists estimate that the lake appeared 10 thousands years ago.

Scientists currently estimate the age of the universe to be 13.75 billion years old.

Scientists estimate only one of 100 turtles lives to become an adult.

The scientists could not estimate the age of the smokers, but they appear to build quickly.

Scientists estimated them to be about the size of an Earth buffalo.