Why 1729 is a magic number? Answer Logically.

What 8 letter word can have a letter taken away and it still makes a word. Take another letter away and it still makes a word. Keep on doing that until you have one letter left. What is the word?

In a university, a professor gave a set of three problems to the three brilliant students of his class. See the image for the questions.

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

Find out a multi-digit number that if multiplied by the number 9 or any of its multiplications products (i.e. 18, 27, 36, 45,..) will result in the multiplication factor repeated (n) number of times.

81 x 9 = 801. What must you do to make the this equation true?

I am not a bull but I have horns.
I am not an ass but I have a pack saddle.
Wherever I go, I leave silver behind me.

Who am I?

what does the below rebus mean?

You are confined in a room and given two metal rods. Out of these two rods, one is magnet and the other is the iron rod. They look starkly similar. You don't have any other metal object in the room.

How will you decide which one of those is magnet?

You need to arrange three 7 and mathematical symbols to form number 1?