What is so fragile that saying its name breaks it?

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

What number comes next in the series?

5 15 5 18 5 24 14 20 _

What Deficiency does the below rebus represent?

VIT_MIN

Count the number of balls in picture below:

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.'

Two batsman each on 94 runs. Seven runs needed to win in last 3 balls. Both make 100*. How?

In the formation, you can see a few arranged matchsticks. Can you form three squares by moving just three matchsticks?

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?

Solve the alphametic puzzle by replacing the alphabet with the number.

S T O R M +
S O L E S
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T O W E L
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