Определить массу пружинного маятника, если период его колебаний равен Т = 0,2 с, а жёсткость пружины k = 200 Н/м.

1) Linda has a toothache. She is going to see the dentist.
2) A group of boys decide to arrange a picnic.They are going to have a nice time.
3) Andrew has a little sister but his parents are busy today. He is going to stay with his sister.
4) It's the weekend. It's sunny and warm.We are going to walk in the park.
5) British students would like to come to Russia in October.We are going to invite them.