How can one talk without saying a single word?

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

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?

What can jump higher than a building?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

You are on a Boat in the mid of a river. You have two cigarettes with you. One of these two you have to light, how will you light the cigarette?

Decode the below four famous ciphers:

8P of the SS
1M of the E
1S of the SS
60M in 1H

A high school has a strange principal. On the first day, he has his students perform an odd opening day ceremony:

There are one thousand lockers and one thousand students in the school. The principal asks the first student to go to every locker and open it. Then he has the second student go to every second locker and close it. The third goes to every third locker and, if it is closed, he opens it, and if it is open, he closes it. The fourth student does this to every fourth locker, and so on. After the process is completed with the thousandth student, how many lockers are open?

What word does this rebus represent?

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Replace the question mark with the number below given a simple math problem.