15; 12; 9; :- арифметическая прогрессия. Является ли членом данной прогрессии число - 40?

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     It seems we all know what tourism is. But “tourism” can be defined differently. For most of us tourism is a great service industry that offers conditions, comfort and 1 … (entertain). For other people it is travel for leisure or recreational purposes and natural ecology. We’d like to suggest you the  last one.

     Our hotel is 2... (situate) in the most 3 …. (picture) landscape you can imagine. Most rooms overlook the Silver Lake, whose 4 …..(deep) is estimated at 200 metres. The lake, always 5 … (mystery) misty in the morning, is surrounded by granite peaks which look so 6 … (approach) that you can hardly believe there is a path to the top of each. The place is completely 7 … (touch) by the tourist industry – you can 8 … (occasion) see an eagle hovering above the lake or a wild goat looking for grass between the rocks.

     The Silver Lake hotel’s unusual 9 … (attract) is doubled by the fact that you can only reach it on foot. The walk up from the bottom of the valley requires some 10 … (fit) but we can guarantee that the view from the hotel's terrace will leave you 11 … (speech). 12… (understand), the place is meant to offer accommodation to climbers and backpackers, rather than motorists and  13… (experience) hikers.
     The hotel offers comfortable, spacious bedrooms and delicious 14 … (special) of the local cuisine. Grilled trout and home-made bread rank among visitors’ favourites. The staff are competent, 15 … (help) and always available. Most important, however, is the unique atmosphere of this place, stylish dining hall, so different from those 16 … (personal) lobbies of modern hotels. The prices are, 17 …(predict), quite high but you are very 18 … (like) to be disappointed by the quality of what is on offer. You will certainly enjoy the 19 … (close) to the nature and the 20 … (simple) and charm of this unusual place.

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усний твір опис процесу праці за власним спостереженням у науковому стилі...допоможіть!!