What does this simple rebus mean?

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

There are forty elephants and they have forty-fore heads. How can this be possible?

There once were seven dwarfs who were all brothers. They were all born two years apart. The youngest dwarf is seven years old. How old is his oldest brother?

What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

Three brothers Jacob, John, and James live in Mexico City. The product of the ages of these brothers is 175. Jacob and John are twins. How old is James?

If you were to put a coin into an empty bottle and then insert a cork into the neck, how could you remove the coin without taking out the cork or breaking the bottle?

Can you spot the man between the coffee bean in the picture below ?

Which three-digit number, made of consecutive digits, like 567, is 2 less than a cube and 2 more than a square?

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?