Ответ:

1. Phenomenal — f) very great or impressive;

2. A long-term trend — d) the trend (the tendency of movement) over a long period of time;

3. A chairman — b) a person in charge of a meeting;

4. To sponsor — a) to give money to a sport event, institution, etc.;

5. A substitute — c) something that you use instead of the usual one;

6. To decline — e) to decrease in importance.