Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

How many cubic feet of dirt are in a hole of one foot deep, three feet long, and two feet wide?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

What have one eye but still cannot see?

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

How can one talk without saying a single word?

500 women soldiers are arranged in an array of ten rows and fifty columns in accordance with their respective heights. Now, the tallest woman from each row is asked to move out in the front. From them, the shortest one is labelled as Alpha. They are then asked to resume their original position.

Now, the shortest woman in each column is asked to come out in front. The tallest among them is labelled as Beta.

Can you find out if Alpha will be taller or Beta?

It is a nine-letter word.
The exact opposite of the phrase "friendly and outgoing"
It contains the word "over".
It starts will a vowel.

What is it?

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

You knock a Table over in the library, and suddenly 20 eyes are looking at you.