What has one letter and starts with an E?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

A man in a car saw a Golden Door, Silver Door and a Bronze Door. What door did he open first?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

Can you make the number 24 by utilizing the numbers 1, 3, 4 and 6? You must use one number only one time and you can use mathematical operation symbols anytime anywhere.

It belongs to you, but other people use it more than you do. What is it?

In the image below, can you find the value of an angle(y)

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

A worker is to perform work for you for seven straight days. In return for his work, you will pay him 1/7th of a bar of gold per day. The worker requires a daily payment of 1/7th of the bar of gold. What and where are the fewest number of cuts to the bar of gold that will allow you to pay him 1/7th each day?

Andrew sees a very rare bird named "Ruppell's vulture". Soon Andrew was dead. Can you explain the mystery, Mr. Sherlock?