What does this simple rebus mean?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

While handling a project, the landscaper is asked by the owner of the mansion that he wants four trees in front of his mansion that are exactly equidistant from each other.

How will he do it?

A few friends are enjoying their sea voyage in a boat full of apples. On the way, they felt hungry and thus decided to eat the apples. Together, they ate two dozen of apples. When they have eaten the apples, will there be any change in the water level?

What's the only room from which no one can enter or leave

Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?

Spot 5 differences in two Christmas tree below:

Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

P is the father of Q and S is the son of R. T is the brother of P and has a daughter U. If R is the sister of P, then what is the relation between U, Q and S?

If 24H in a D => 24 hours in a day.
What does "64S on CB" stand for?