If all Goats are Sheep and all Sheep are Deers, are all Deers Goats ?

I come in different shapes and sizes.
Parts of me are curved, other parts are straight.
You can put me anywhere you like,
but there is only one right place for me.
What am I?

An artist while painting a scenic beauty, decides to paint three layers of blue colour on the sky.

Which layer will go on the first?

John is selling fruits.
He sells grapes at $30, Dates $25, and a Wolfberry $45.
At what price does he sell fig?

PS: Logical Thinking

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

What can you see in the middle of March and April that you can never see in any other month?

There are four 3-link chains. All you have to do is join them into a big 12-link chain. For joining two closed links, one of the links must be cut and placed onto the other link for closing.

How many minimum links will you have to cut to make the big chain?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

A girl is twice as old as her brother and half as old as her father. In 50 years, her brother will be half as old as his father. How old is the daughter now?

How do you go from 98 to 720 using just one letter?