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

John is the son of Jacob.
So,
Jacob is the_____of John's father?

In a supermarket, there is an intelligent glass pane before a refrigerating unit. This glass pane allows cherries and apples through it but does not allow grapes and Orange to pass through it.

Can you identify the rule that the glass pane is following?

Find The Next Number in the series:

12 13 15 17 111 113 117 119 123 ?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

Four men were in a boat on the lake. The boat turns over, and all four men sink to the bottom of the lake, yet not a single man got wet! Why?

On a magical land of Mexico , all the animal in the land are rational.

There are 10 tigers and one goat.
Tiger can eat goat but since it's a magical land , the tiger who eats the goat , turns into goat and then can be eaten by the remaining tiger(s).

If we leave them for some time then how many goat and tiger will be there , when we come back ?

What begins with T, ends with T, and has T in it?

Can you count the number of triangles inside a triangle?

I cry without having a voice.
I fly without having wings.
I bite without having teeth.
I whisper without a mouth.

Who am I?