помогите плз) в параллелограмме ABCDсторона BC равна 18дм и сост. 3/11 периметра.Найти стороны параллелограмма.

верно ли утверждение "Окружность имеет бесконечно много центров симметрии."

Помогите,прошу!

Find the mistakes-

1.But for the conference a few days ago Philip would never come back to his native city.

2.But for your laziness,the rezult of the work would have been much better.

3.If only they had had a pet now.

4.If I knew the truth then.

5.If it did not rain yesterday,we would enjoy the trip more.

6.If it had been summer.there would have been a lot of flowers in the country.

7.But for my parents I would not visit Paris last year.

8.But for my mother is telephone call,I would have worried now.

9.If it nad been summer now.

10.If only I visited Great Britain last year.

11.If my friend told me the truth then,I would forget the whole story.

12.If I had had enough time now,I would have worked on the computer.

  Заранее спасибо

стороны треугольника относяться как 3:4:6. соединив середины всех сторон,получим треугольник,периметр которого равен 5,2м.нати стороны данного треугольника.  помогите плз)