What does below chemistry rebus means?

What numbers should go on the bottom line?
3 6 9 15
8 2 10 12
11 8 19 27
19 10 29 39
? ? ? ?

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

My location can be determined by the below rebus.
So where am i ?

I am green and found in the forest and have needles instead of leaves. What am I?
Hint 1: It can be used for Christmas decorations.
Hint 2: I have a strong, scent that is used in air fresheners.

A man walked into a pub and went straight towards the Barman. He asked for a dirty martini from the Barman. The Barman thought something and then pulled out a pistol from his drawer and aimed it directly at the man. Why did he do that?

If 1+9+8=1, what is 2+8+9?

Next Number in the Series,

5, 16, 49, 104, ?

I start and end with 500 and carry a 5 in my heart. But I require the first letter and the first number to be complete. I am the name of a King.

Who am I ?