Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

What has many keys but can’t open a single lock?

I am soft and cuddly that soothe your heart. But, If you pick my last name I am going to tear you all apart. Who am I?

A man walked into a pub and went straight towards the Barman. He asked for a dirty martini from the Barman. The Barman thought something and then pulled out a pistol from his drawer and aimed it directly at the man. Why did he do that?

A man is shown a portrait painting. He looks closely, then tells, “Brothers and sisters have I none, but that man’s father is my father’s son!” Who is the man in the portrait?

A Doctor always sneezes before the rain. Doctor sneezes, Will it rain?

It belongs to you, but other people use it more than you do. What is it?

There are 100 bulbs in a room. 100 strangers have been accumulated in the adjacent room. The first one goes and lights up every bulb. The second one goes and switches off all the even-numbered bulbs - second, fourth, sixth... and so on. The third one goes and reverses the current position of every third bulb (third, sixth, ninth? and so on.) i.e. if the bulb is lit, he switches it off and if the bulb is off, he switches it on. All the 100 strangers progress similarly.

After the last person has done what he wanted, which bulbs will be lit and which ones will be switched off?