Do You See It?

What has 13 hearts but no other organs?

I cannot talk, but I always reply when spoken to. What am I?

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

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

In four steps you need to move the word 'cold' From 'warm' by replacing one alphabet at a time such that every word formed at each step is acceptable in English Dictionary.

A convention is held where all the big logicians are summoned. The master places a band on everyone's forehead. Now all of them can see others bands but can't see his own. Then they are told that there are different colours of bands. All the logicians sit in circle and they are further explained that a bell will ring at regular intervals. The moment when a logician knew the colour of band on his forehead, he will leave at the next bell. If anyone leaves at the wrong bell, he will be disqualified.

The master assures the logicians that the puzzle will not be impossible for anyone of them. How will the logicians manage ?

Can you find the ages of a son, father and grandfather based on the following facts?
The sum of the ages of grandfather, father and son is 140 years.
The age of the son in months is the same as the grandfather in years.
The age of the son in days is the same as the father in weeks.

What jumps when it walks and sits when it stands?

The product of three consecutive numbers is 7980.
Then the sum of these consecutive numbers would be?