Can you name three consecutive days without using the words Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, or Sunday?

Can you name an animal whose killing cannot be performed without spilling your own blood?

A professor thinks of two consecutive numbers between 1 and 10.
'A' knows the 1st number and 'B' knows the second number

A: I do not know your number.
B: Nor do I know your number.
A: Now I know.

What are the four solutions for this?

John was piloting a plane behind a car but was never able to overtake it. Why?

What English word has three consecutive double letters?

What animal walks on four legs in the morning, two legs during the day, and three legs in the evening?

Oedipus, the king of Thebes, figured out the answer to the riddle:

What is common among 11, 69, and 88?

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

The answer I give is yes, but what I mean is no. What was the question?

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.