cos( α+ π) + sin ( α- 3π/2) - ctg( π/2 + α)*tg( 3π/2 + α)=?

sin 420+ cos(-390) + tg(-1230) - ctg420=?

sin 5π /18*cos π /9 - sin π/9 * cos 5 π/ 18 =?

tg² α + sin²α - 1/ cos²α=?

Закончите уравнения хим.реакций: N2+H2=

NH3+HNO3=; 

NH3+O2 =; 

CaCo3+HCl=; 

CO + CuO =; 

Me+H2SO4 =; 

Cu+HNO3 =;

почему при использовании ядохимикатов для борьбы с сельскохозяйственными вредителями погибают прежде всего хищные птицы?

Определите значение понятий "колония","протекторат","метрополия".Приведите примеры.

Task Two. (Total score – 9)

Put the verbs in brackets in the appropriate non-finite form (Infinitive, Gerund or Participle).

            When David decided (1) (give up) his job and sold all his possessions, everyone thought that he was mad. But, as it turned out, he was just       the first of many friends (2) (do) this. In fact, escaping the pressures of everyday working life has become a priority for many people these days. They can’t stand the idea of (3) (work) until they are 65. They would rather (4) (live) life to the full now, before they are too old (5) (enjoy) it. (6) (buy) a motorcycle and (7) (tour) the world is a popular option. Personally, one fancies (8) (sail) around the world in a yacht. As for David, he bought a house in a little country village and spends his time (9) (walk) around the village and talking with his neighbours.

Task Four. (Total score – 9)

Read the text. Use the word given in brackets to form a word that fits the space. There is an example in the beginning (0).

School Now and Then

            Parents and teachers are always making (0) (compare) comparison between the time when they were (1) (child) and the present (2) (generate). They say everything was better than it is today, especially in (3) (educate). For example, they say they used to work much (4) (hard) in school, and that nowadays, we aren’t very interested. I (5) (agree), because we spend hours every day doing homework after our lessons or (6) (revise) for (7) (examine). I wonder if our parents really had to study so much after school every day. In my opinion, it is no (8) (exaggerate) to say we have forgotten how to play. I think one reason why kids (9) (behave) in class is because they need to get rid of stress.