Найдите пары изомеров. Укажите тип изомерии и названия вещества

4. Собственная скорость моторной лодки равна 12,6 км/ч, скорость течения реки 1,8 км/ч. Сначала лодка плыла
0,5 ч против течения реки, а затем 2,5 ч по озеру. Какой путь проплыла лодка за все это время?

Помогите решить системы уравнений.

А)   3x-5=4

       5x+2y=12

Б)   y-2x=4

      x-3y=-2

5(корень из 12)*4(корень из 2)/25(корень из 6)

Choose the right verb form to complete the sentence

1.If the Hogs(did not travel/had not travelled)in Africa about 5 years ago,their children(would not know/would not have known)so much about African fauna.

2.If I (were not/had not been)encouraged by my parents to do English when I was at school,I(would not be/would not have been) a succesful translator.

3.James ambition has always been to become a singer.If he(did not try/had not tried)to learn to sing when he was younger,he(would/would have done)it now.

4.If Jan(went/had gone)to university when he was younger,he (would be/would have been)a lawyer now.

5.If Melissa(did not have/had not had)an interview last Monday,she(would not have/would not have had)a regular job now.

6.If Nick(did not follow/had not followed)his friend is example,he(would not be/would not have been)a very good surgeon.