What has no start, end, or centre?

What does this rebus mean?

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TIME

Only one colour, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

A mathematics teacher took exams for his students. Out of the total students, 25% passed both the tests included in the exam. However, only 42% were able to clear the first test.

Can you find out the percentage of those students who passed the first test and also passed the second test?

How can you tell a raw egg from a hard-boiled egg?

I am never scared but became petrified and can’t live in a house but would die to make one. What am I?

What number do you get when you multiply all of the numbers on a telephone's number pad?

In a contest, four fruits (an apple, a banana, an orange, and a pear) have been placed in four closed boxes (one fruit per box). People may guess which fruit is in which box. 123 people participate in the contest. When the boxes are opened, it turns out that 43 people have guessed none of the fruits correctly, 39 people have guessed one fruit correctly, and 31 people have guessed two fruits correctly.
How many people have guessed three fruits correctly, and how many people have guessed four fruits correctly

Can you identify the direction in which this bus is moving; left or right?

Hint: The bus is moving on the roads of London.

What is the word or phrase?