What is in seasons, seconds, centuries and minutes but not in decades, years or days?

When it's bad luck to meet a black cat?

What are the 50th, 63rd and 100th numbers in the sequence below?
4, 5, 8, 8, 9, 9, 12, 13, 13, 13, 17, 18, ...

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

The dirtier I get, the whiter I look. Who am I?

I am an eight letter word and I am a computer terminology.
The second, third and fourth letters make an animal.
The fourth, fifth, sixth, seventh and eighth letters make a weapon.
The first, second, third and fourth letters can be taken as an outcome of any exam.
The fifth, sixth, seventh and eighth letter combine to form a high end typing software.

Can you tell who am I ?

Consider this: Arnold Schwarzenegger has a big one. Michael J. Fox has a small one. Prince doesn’t have one. The Pope has one but never uses it. Bill Clinton has one and uses it all the time. What is it?

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?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

What breaks yet never falls, and what falls yet never breaks?