Answer:
I jump when I walk and sit when I stand. What am I?
What comes once in a year twice in a week but never in a day?
What has many teeth but can't bite?
I am a mini solar powered computer
I am a seven letter word. I am very heavy. Take away two letters from me and you will get eight. Take away one letter from me and you will get 80. What word am I?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.