51.   Computers are increasingly used for data analysis.

52.   Coupons generally offer the best savings when used for coast-to-coast or other long-distance domestic flights.

53.   Designed principally for classroom use but can be used for self-study.

54.   Door-to-door sales methods are used for a variety of products, from vacuum cleaners and household goods to cosmetics or double glazing.

55.   Drinks are hand-shaken and only freshly squeezed juices are used for mixing.

56.   During the International Festival it is used for Apron-stage theatrical performances.

57.   Each group is used for a different purpose, to inactivate bacteria or block the action of viruses, for example.

58.   Elsewhere, the tree had grown randomly at lower elevations, and the nut was used for local consumption.

59.   Exponential smoothing would again normally be used for short term forecasting, for periods up to six months ahead.