Solve this

It's a 7 Letter Word,
If we remove 1 letter from it, it remains same.
If we remove 2 letter from it, it remains same.
If we remove 3 letter from it, it remains same.
If we remove all the letters from it, still it remains same.

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1. You buy it to eat, but you don't eat it. What is it?

2. What goes up and down without moving?
3. What has holes but holds water?
4. I start with an E, end with an E and I only have one letter, what am I?
5. I have got three eyes and all are in a straight line. When my red eye opens, everything freezes.
6. I am a six letter word. Subtract one letter and twelve will remain. Who am I?
7. When I am open I am U-shaped but when I am closed I am V-shaped. Who am I?
8. I am a four letter word. I am an animal. You use me to call your dear ones. Who am I?
9. I am a fruit. I am tasty and provide lots of energy. You can find also me in a calendar. Who am I?
10. I have a thumb and four fingers, but I have no flesh or bone. Who am I?