What does this rebus mean?

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TIME

Prove that twice of ten is the same as twice of eleven.

If 1+9+8=1, what is 2+8+9?

Decode the below four famous ciphers:

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

What has no start, end, or centre?

If two fifty-foot ropes are suspended from a forty-foot ceiling that is twenty feet apart, how much rope will you be able to steal if you have a knife?

A bag contains 64 balls of eight different colours. There are eight of each colour (including red). What is the least number you would have to pick, without looking, to be sure of selecting 3 red balls?

When a clock is observed, the hour hand is at a minute mark and the minutes hand is six minutes ahead of it.

When the clock is observed again after some time, the hour hand is precisely on a different minute mark and the minute hand is seven minutes ahead of it.

Can you calculate how much time has elapsed between the two observations?

In a supermarket, there is an intelligent glass pane before a refrigerating unit. This glass pane allows cherries and apples through it but does not allow grapes and Orange to pass through it.

Can you identify the rule that the glass pane is following?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?