It seems the Earth's climate passes a _______ beyond which climate change accelerates with the help of positive feedbacks - vicious circles of warming.

Amazon is swiftly becoming a ______ retailer by letting other companies sell products on its site.

During America's last Thanksgiving weekend, Amazon's sales of consumer electronics in the United States ________ its book sales for the first time in its history.

Far from becoming ______ online shoppers are very demanding.

Online shoppers now read not only the sales _______ but also reviews from previous purchasers.

The stores run by Sony and Apple, for instance, are there for people to try out _______ and to ask questions to knowledgeable staff.

The ocean is capable of removing carbon, and quickly, but this natural process can be easily ______.

Other transformations in the retail business are ______ to follow the trend of Amazon.

Smarter consumers know which products have a good _______ and which do not.

If customers are disappointed, a few _____ of the mouse will take them to places where they can let the world know.

Greenhouse gases are being released into the atmosphere 30 times faster than the time when the Earth experienced a ______ episode of global warming.

A study comparing the rate at which carbon dioxide and methane are being _______ now, 55 has found dramatic differences in the speed of release.