Насколько надо растянуть недеформированную пружину жёсткостью 100 Н/м, чтобы её потенциальная энергия стала равной 0,5 Дж?

1) Kiev was the capital of Ancient Rus long time ago.
2) There were a lot of different rulers there.
3) A lot of famous people buried there.
4) Kiev was a russian city long ago.
5) Kiev became the capital of Ukraine many years ago.

1) Michael Jackson was good singer.
2) He had a band with his brothers.
3) He was handsome.
4) He had  difficult relations with his father.
5) He was the king of pop music.