Can anyone tell me a word in the English dictionary which has a silent 'z'?

A man hijacks an aeroplane transporting both passengers(8 of them) and valuable cargo. After taking the cargo, the man demands nine parachutes, puts one of them on, and jumps, leaving the other eight behind. Why did he want eight?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

You have three orange, two pink and five purple balls in the drawer beside your bed. There is no electricity and the room is entirely dark. How many balls must you take out to ensure at least one ball of each colour at least?

Solve The below Equation:

ALFA + BETA + GAMA = DELTA

Andrew’s doctor gives him three pills and tells him to take one every half hour. How much time will have passed by the time Andrew’s taken all three pills?

The day before yesterday I was 25 and the next year I will be 28. This is true only one day in a year. What day is my birthday?

A Child was born in Lahore, Pakistan. Still, the child is not a Pakistani citizen. why?

I make two people out of one. What am I?

You are an expert on paranormal activity and have been hired to locate a spirit haunting an old resort hotel. Strong signs indicate that the spirit lies behind one of four doors. The inscriptions on each door read as follows:

Door A: It's behind B or C
Door B: Its behind A or D
Door C: It's in here
Door D: It's not in here

Your psychic powers have told you three of the inscriptions are false, and one is true. Behind which door will you find the spirit?