Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

With the help clues provided in the image, can you find the 5 digit key?

How many letters are in the alphabet?

You are on your way to visit your Friend, who lives at the end of the hill. It is his birthday, and you want to give him the cakes you have made. Between your house and his house, you have to cross 5 bridges, and as it goes in the land of make believe, there is a troll under every bridge! Each troll, quite rightly, insists that you pay a troll toll. Before you can cross their bridge, you have to give them half of the cakes you are carrying, but as they are kind trolls, they each give you back a single cake. How many cakes do you have to leave home to make sure that you arrive at a friend's house with exactly two

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

Imagine you are in a room with no windows or doors. How will you get out?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

Replace The Question Mark Below With the Correct Number.

2 {38} 3
4 {1524} 5
6 {3548} 7
8 {????} 9