A word I know has six letters it contains, remove one letter and 12 remain. What is it?

15 caves are arranged in a circle at the temple of doom. One of these caves has the treasure of gems and wealth. Each day the treasure keepers can move the treasure to an adjacent cave or can keep it in the same cave. Every day two treasure seekers visit the place and have enough time to enter any two caves of their choice.

How do the treasure seekers ensure that they find the treasure in the minimum number of possible days?

Sally lives in a place where six months of the year is mild summer and the temperature drops significantly the other six months. She owns a lake where there is a small island. She wants to build a house on the island and needs to get materials there. She doesn’t have a boat, plane, or anything to transport them to the island. How does Sally solve this problem?

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

I make two people out of one. What am I?

Today is John's birthday.
A year ago, John had five candles and he lit all the candles except the one at the last.
Now he is going to light all the candles.

How old is John Today?

(He is not five today.....)

I travel all around the world but always stay in the corner. What am I?

How many minutes are there in Feb 2017?

Note: The shortest answer is the correct answer.

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

The following four words might seem abrupt to you. But you can make them meaningful by just adding vowels.
RDSH
GGPLNT
TMT
NN

Hint: All of them are vegetables.