Science Riddle

If I have it, I don't share it. If I share it, I don't have it. What is it?

I am an odd number. Take away a letter and I become even. What number am I?

There's only one word in the dictionaruy that's spelled wrong. What is it?

If there are three apples and you take away two, how many apples do you have?

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

What is the center of gravity?

What has legs but cannot walk?

What kind of cup doesn't hold water?

Tom's father has three sons, Jim, John, and what's the third one's name?

What is the end of everything?

What month of the year has 28 days?

What is so fragile that saying its name breaks it?

What's the capital of France?

What has to be broken before you use it?

Which weighs more, a ton of concrete or a ton of feathers