What number comes next in the series?

5 15 5 18 5 24 14 20 _

I am a type of vehicle that has two wheels and is powered by humans. What am I?
Hint 1: You can ride me for exercise.
Hint 2: I am environment-friendly.

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

What number does the below three word/phrase identify and why?
1. Deck
2. Year
3. Singing in the Rain

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

John drives to his office at 20km/hr. After reaching the office, he realizes that today is a holiday. He went back at an average speed of 30km/hr. Discounting the time spent in the stoppage what was the average speed of his journey?

On a bus, there is a 26-year-old pregnant lady.
A 30-year-old policeman.
A 52-year-old random woman.
And the 65-year-old driver.

Who is the youngest?

John is asked to stand behind Jacob and Jacob is asked to stand behind John. Both of them feel confused about it and don't know what to do?

But it is quite possible, do you know how?

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

What Time Should the last watch show in the below figure?