What common phrase is represented by the below lines

Easy going:
Weak, 'I'm going.'
Tough, 'I'm staying.'

Medium going:
Weak, 'I'm going.'
Tough, 'I'm staying.'

Tough going:
Weak, 'I can't do it, I'm staying!'
Tough, 'Let's get going.'

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.

What is the fastest way to double your money?

What word begins and ends with an E, but has only one letter?

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

A boy and his father are caught in a traffic accident, and the father dies. Immediately the boy is rushed to a hospital, suffering from injuries. But the attending surgeon at the hospital, upon seeing the boy, says 'I cannot operate. This boy is my son.' How is this situation explained?

John’s parents have three sons: Snap, Crackle, and what’s the name of the third son?

What is the riddle which can be asked all day with a different correct answer each time.

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

There's a day, that comes around once a year.
To celebrate the man, you hold dear.
He gave you life, love and will pick you up if you fall.
When it comes to guys like him, He's the best of all.
Who is he?