Presentation about refrigeration

A. why they were first created

B. how the ice was kept frozen

C. where they were located

A. It became a commercial business.

B. It used snow from nearby.

C. It took a long time to become popular.

A. the complexity of the technology.

B. the fact that some are disposed of irresponsibly.

C. the large number that quickly break down.

A. They are generally good value for money.

B. There are plenty of useful variations.

C. They are more useful than other domestic appliances.