Replace the question mark with the correct number in the below-given picture?

A girl was sitting in her hotel room when she heard a knock on the door. She opened the door and found that a man was standing outside.
The man said, "Oh! I am really sorry, I thought this was my room."
He then walked through the corridor to the elevator. The girl did not know the man. She closed her door and called security asking them to apprehend the man.
What made her suspicious of that man? He might have been genuinely mistaken.

Count the number of triangles in the below picture?

What time is it when an elephant sits on a fence?

What does a man do only once in his lifetime, but women do once a year after they are 29?

The current time can be represented by below textual rebus.

0
=========
B.Sc
LLB

Can you tell us the current time?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

Different lights make me strange by changing me into different sizes. What am I?

Three fair coins are tossed in the air and they land with heads up. Can you calculate the chances that when they are tossed again, two coins will again land with heads up?

A little girl goes to the store and buys one dozen eggs. As she is going home, all but three break. How many eggs are left unbroken?