By including only four matchsticks in below picture, you have to make "Four Triangles And Two Squares"

Complete the following series. It.s very logical:

1, 4, 5, 6, 7, 9, 11, __?

You can hear me, but you can't touch or see me.

What am I?

A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?

There are three identical triplets sisters. Demi is the oldest of them all and she always speaks the truth. Diana is the next one who is a liar always. Drew, the youngest of them all speaks both truth and lies randomly.

On a rainy day, a family friend Victor visited them. Since there were starkly identical, he was not able to recognize them. Thus to clarify, he asked one question to each one of them.

He started with the one standing on the left and asked, 'Which sister is in the middle of you three?' She answered, 'That's Demi.'

Then, he asked the one standing in the middle, 'What is your name?' She answered, 'I am Drew.'

Finally, he asked the one standing on the right, 'Who is standing in the middle?' She answered, 'She is Diana.'

Victor was left baffled. He asked the questions three times and received different answers every time.

Can you tell who was who?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

Which is faster, Heat or Cold ? Explain.

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?

He loves to dance, twist and prance, he shakes his tail, and as a way he sails, wingless he flies into the sky. What is he?

In case you were starting to feel confident, this one was meant for third graders in Vietnam. The answer is 66, but we don't blame you for scratching your head about how they got there.