What work can one never finish?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

Find out which of the given views in the picture is accurately the top view of the given pyramid.

When you stop to look, you can always see me. But if you try to touch me, you can never feel me. Although you walk towards me, I remain the same distance from you. What am I?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

I am a type of food that is often found in the fridge and can be white in colour. What I am?
Hint 1: I am a dairy product.
Hint 2: You can spread me on the bread.

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?

A man has eighty-one cows ( numbered 1,2,3...81 as such). The beauty is that cow no. 1 gives 1ltr of milk, cow no. 2 gives 2ltrs of milk and so on. The man wants to equally distribute the cows among his nine sons so that each one of them gets the same quantity of milk.

I can be cracked, made, told, and played. What am I?

I shave every day, but my beard stays the same. What am I?