Riddles and brain teasers

How many letters are there in 'the English alphabet'?

What goes up but doesn't come back down?

A word I know, six letters it contains, remove one letter and 12 remains, what is it?

What is full of holes but still holds water?

What has hands but doesn't clap?

What begins with an E but only has one letter?

Mr. Blue lives in a Blue house. Mrs. Yellow lives in a Yellow House. Who lives in the White House?

What travels around the world but stays in one place?

What starts with T, is filled with T and ends in T?