RIDDLE me this amigos

Hello my riddlers and riddlies see if you can get without looking.

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1.Name an eight letter word that has kst in the middle, in the beginning, and at the end

Answer at bottom.

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2.A boy has as many sisters as brothers, but each sister has only half as many sisters as brothers.

How many brothers and sisters are there in the family?

Answer at bottom

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3.What is the difference between a school boy studying and a farmer watching his cattle?

Answer at bottom

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4.What is the next 3 letters in this riddle? o t t f f s s _ _ _

Answer: at bottom

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5.Marking mortal privation, when firmly in place. An enduring summation, inscribed in my face.

What am I?

Answer at bottom.

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1.Inkstand - kst is in the middle. "In" is the beginning, and "and" ends the word.
2.Four brothers and three sisters.
3.One is stocking his mind, while the other is minding his stock
4.e n t They represent the first letter when writing the numbers one thru ten.
5.A Tombstone.