What does below rebus means ?

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

Identify Me

Hint1: I am a god
Hint 2: I am a planet
Hint 3: measurer of heat

Can you count the number of triangles in the picture below?

Below toothpicks/matchsticks indicate the group of fishes moving from west to east direction. Can you make them move from east to west by just moving three toothpicks/matchsticks?

A network of 20 x 10 squares is given to you.

Can you calculate how many unique squares and rectangles can be formed combining two or more individual squares ?

You need to arrange three 7 and mathematical symbols to form number 1?

You have two bottles of pills marked with labels A and B. The pills are identical. The doctor has asked you to take one A pill and one B pill daily. You cant take more or less than that.

While taking out the pills one day, you took out one pill from A and by mistake took out two from B. You have no idea which pill is which now.

You cant throw away the expensive pills. What will you do now?

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

A mules travels the same distance daily.
I noticed that two of his legs travels 10km and the remaining two travels 12km.
Obviously two mules legs cannot be a 2km ahead of the other 2.

The mules is perfectly normal. So how come this be true ?