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

(a)  

What is seen in the middle of March and April that can't be seen at the beginning or end of either month?

(a)  

I have to be opened, but I don't have a lid or a key to get in. What am I?

(a)  

What can travel around the world while staying in a corner?

(a)  

I am an odd number. Take away a letter and I become even. What number am I?

(a)  

I have no life, but I can die. What am I?”

(a)  

What has a bed but never sleeps, can run but never walks, and has a bank but no money?”

(a)  

What begins with T, finishes with T, and has “T” in it?”

(a)  

What goes up but never goes back down?”

(a)